| Message ID | FE07E514-2D96-467A-A6AC-F1BB11FCF953@sandoe.co.uk |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] C++ : Add the -stdlib= option. | expand |
On 12/22/20 3:39 PM, Iain Sandoe wrote: > Hi Jason, > > Jason Merrill <jason@redhat.com> wrote: > >> On 11/11/20 3:58 PM, Iain Sandoe wrote: > >>> This option allows the user to specify alternate C++ runtime libraries, >>> for example when a platform uses libc++ as the installed C++ runtime. >>> It is the same spelling as a clang option that allows that to use libstdc++. >>> I have had this patch for some time now (more than a year) on Darwin >>> branches. >>> > >>> + /* Which standard library to link. >>> + 1 = libstdc++ >>> + 2 = libc++. */ >>> + int which_library = 1; >> >> Even if this variable is an int, let's introduce an enum for comparing it to specific values. > > done - it is also noted that it must track the enum in the opt file. > >>> @@ -264,6 +293,8 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, >>> /* Add one for shared_libgcc or extra static library. */ >>> num_args = argc + added + need_math + (library > 0) * 4 + 1; >>> + if (which_library > 1 && LIBCXXABI != NULL) >>> + num_args += 4; >> >> Why does libc++ need more args than libstdc++? Please add a comment. > > done (JFTR, it’s because libc++ doesn’t include the abi library for most platforms, so that also has to be > appended to the link line). > >>> +#ifdef GPLUSPLUS_LIBCXX_INCLUDE_DIR >>> + /* Pick up libc++ include files, if we have -stdlib=libc++. */ >>> + { GPLUSPLUS_LIBCXX_INCLUDE_DIR, "G++", 2, 1, >> >> If you're going to give cplusplus a non-boolean value, the comment in cppdefault.h needs to reflect that. > > done. > > (re-)tested on x86_64-darwin{11,16,17,19, 20} with the installed libc++ and x86_64-linux-gnu with an > LLVM-9 build. Bootstrapped and smoke-tested for libc++ (regular testing for libstdc++). > > OK for master now? OK. > thanks > Iain > > ==== revised patch > > > This option allows the user to specifiy alternate C++ runtime libraries, > for example when a platform uses libc++ as the installed C++ runtime. > > We introduce the command line option: -stdlib= which is the user-facing > mechanism to select the C++ runtime to be used when compiling and linking > code. This is the same option spelling as that used by clang to allow the > use of libstdc++. > > The availability (and thus function) of the option are a configure-time > choice using the configuration control: > --with-gxx-libcxx-include-dir= > > Specification of the path for the libc++ headers, enables the -stdlib= > option (using the path as given), default values are set when the path > is unconfigured. > > If --with-gxx-libcxx-include-dir is given together with --with-sysroot=, > then we test to see if the include path starts with the sysroot and, if so, > record the sysroot-relative component as the local path. At runtime, we > prepend the sysroot that is actually active. > > At link time, we use the C++ runtime in force and (if that is libc++) also > append the libc++abi ABI library. As for other cases, if a target sets the > name pointer for the ABI library to NULL the G++ driver will omit it from > the link line. > > gcc/ChangeLog: > > * configure.ac: Add gxx-libcxx-include-dir handled > in the same way as the regular cxx header directory. > * Makefile.in: Regenerated. > * config.in: Likewise. > * configure: Likewise. > * cppdefault.c: Pick up libc++ headers if the option > is enabled. > * cppdefault.h (struct default_include): Amend comments > to reflect the extended use of the cplusplus field. > * incpath.c (add_standard_paths): Allow for multiple > c++ header include path variants. > * doc/invoke.texi: Document the -stdlib= option. > > gcc/c-family/ChangeLog: > > * c.opt: Add -stdlib= option and enumerations for > libstdc++ and libc++. > > gcc/cp/ChangeLog: > > * g++spec.c (LIBCXX, LIBCXX_PROFILE, LIBCXX_STATIC): New. > (LIBCXXABI, LIBCXXABI_PROFILE, LIBCXXABI_STATIC): New. > (enum stdcxxlib_kind): New. > (lang_specific_driver): Allow selection amongst multiple > c++ runtime libraries. > --- > gcc/Makefile.in | 6 ++++ > gcc/c-family/c.opt | 14 +++++++++ > gcc/config.in | 6 ++++ > gcc/configure | 57 ++++++++++++++++++++++++++++++++-- > gcc/configure.ac | 44 +++++++++++++++++++++++++++ > gcc/cp/g++spec.c | 74 ++++++++++++++++++++++++++++++++++++++++----- > gcc/cppdefault.c | 5 +++ > gcc/cppdefault.h | 7 ++++- > gcc/doc/invoke.texi | 10 ++++++ > gcc/incpath.c | 6 ++-- > 10 files changed, 216 insertions(+), 13 deletions(-) > > diff --git a/gcc/Makefile.in b/gcc/Makefile.in > index 178e4eaa513..6847022f108 100644 > --- a/gcc/Makefile.in > +++ b/gcc/Makefile.in > @@ -679,6 +679,9 @@ build_tooldir = $(exec_prefix)/$(target_noncanonical) > # Directory in which the compiler finds target-independent g++ includes. > gcc_gxx_include_dir = @gcc_gxx_include_dir@ > gcc_gxx_include_dir_add_sysroot = @gcc_gxx_include_dir_add_sysroot@ > +# Directory in which the compiler finds libc++ includes. > +gcc_gxx_libcxx_include_dir = @gcc_gxx_libcxx_include_dir@ > +gcc_gxx_libcxx_include_dir_add_sysroot = @gcc_gxx_libcxx_include_dir_add_sysroot@ > # Directory to search for site-specific includes. > local_includedir = $(local_prefix)/include > includedir = $(prefix)/include > @@ -1185,6 +1188,7 @@ FLAGS_TO_PASS = \ > "prefix=$(prefix)" \ > "local_prefix=$(local_prefix)" \ > "gxx_include_dir=$(gcc_gxx_include_dir)" \ > + "gxx_libcxx_include_dir=$(gcc_gxx_libcxx_include_dir)" \ > "build_tooldir=$(build_tooldir)" \ > "gcc_tooldir=$(gcc_tooldir)" \ > "bindir=$(bindir)" \ > @@ -3004,6 +3008,8 @@ PREPROCESSOR_DEFINES = \ > -DGPLUSPLUS_INCLUDE_DIR_ADD_SYSROOT=$(gcc_gxx_include_dir_add_sysroot) \ > -DGPLUSPLUS_TOOL_INCLUDE_DIR=\"$(gcc_gxx_include_dir)/$(target_noncanonical)\" \ > -DGPLUSPLUS_BACKWARD_INCLUDE_DIR=\"$(gcc_gxx_include_dir)/backward\" \ > + -DGPLUSPLUS_LIBCXX_INCLUDE_DIR=\"$(gcc_gxx_libcxx_include_dir)\" \ > + -DGPLUSPLUS_LIBCXX_INCLUDE_DIR_ADD_SYSROOT=$(gcc_gxx_libcxx_include_dir_add_sysroot) \ > -DLOCAL_INCLUDE_DIR=\"$(local_includedir)\" \ > -DCROSS_INCLUDE_DIR=\"$(CROSS_SYSTEM_HEADER_DIR)\" \ > -DTOOL_INCLUDE_DIR=\"$(gcc_tooldir)/include\" \ > diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt > index 21d8cd03709..e0c322f61ae 100644 > --- a/gcc/c-family/c.opt > +++ b/gcc/c-family/c.opt > @@ -2356,6 +2356,20 @@ std=iso9899:2018 > C ObjC Alias(std=c17) > Conform to the ISO 2017 C standard (published in 2018). > > +stdlib= > +Driver C++ ObjC++ Common Condition(ENABLE_STDLIB_OPTION) Var(flag_stdlib_kind) Joined Enum(stdlib_kind) RejectNegative Init(1) > +-stdlib=[libstdc++|libc++] The standard library to be used for C++ headers > +and runtime. > + > +Enum > +Name(stdlib_kind) Type(int) > + > +EnumValue > +Enum(stdlib_kind) String(libstdc++) Value(1) > + > +EnumValue > +Enum(stdlib_kind) String(libc++) Value(2) > + > traditional > Driver > > diff --git a/gcc/config.in b/gcc/config.in > index 216505abd2c..10a13cde586 100644 > --- a/gcc/config.in > +++ b/gcc/config.in > @@ -240,6 +240,12 @@ > standards-compatible mode on s390 targets. */ > #undef ENABLE_S390_EXCESS_FLOAT_PRECISION > > +/* Define if the -stdlib= option should be enabled. */ > +#ifndef USED_FOR_TARGET > +#undef ENABLE_STDLIB_OPTION > +#endif > + > + > /* Define if you want all operations on trees (the basic data structure of the > front ends) to be checked for dynamic type safety at runtime. This is > moderately expensive. */ > diff --git a/gcc/configure b/gcc/configure > index fbe92089640..ee9760354b6 100755 > --- a/gcc/configure > +++ b/gcc/configure > @@ -675,6 +675,8 @@ host_xm_defines > host_xm_include_list > host_xm_file_list > host_exeext > +gcc_gxx_libcxx_include_dir_add_sysroot > +gcc_gxx_libcxx_include_dir > gcc_gxx_include_dir_add_sysroot > gcc_gxx_include_dir > gcc_config_arguments > @@ -937,6 +939,7 @@ with_native_system_header_dir > with_build_sysroot > with_sysroot > with_gxx_include_dir > +with_gxx_libcxx_include_dir > with_cpp_install_dir > enable_generated_files_in_srcdir > with_gnu_ld > @@ -1801,6 +1804,8 @@ Optional Packages: > --with-sysroot[=DIR] search for usr/lib, usr/include, et al, within DIR > --with-gxx-include-dir=DIR > specifies directory to put g++ header files > + --with-gxx-libcxx-include-dir=DIR > + specifies directory to find libc++ header files > --with-cpp-install-dir=DIR > install the user visible C preprocessor in DIR > (relative to PREFIX) as well as PREFIX/bin > @@ -3731,6 +3736,52 @@ elif test "${with_sysroot+set}" = set; then > fi > fi > > +# Configuration for an alternate set of C++ headers. > +gcc_gxx_libcxx_include_dir= > +# Specify the alternate g++ header file directory > + > +# Check whether --with-gxx-libcxx-include-dir was given. > +if test "${with_gxx_libcxx_include_dir+set}" = set; then : > + withval=$with_gxx_libcxx_include_dir; case "${withval}" in > +yes) as_fn_error $? "bad value ${withval} given for libc++ include directory" "$LINENO" 5 ;; > +no) ;; > +*) gcc_gxx_libcxx_include_dir=$with_gxx_libcxx_include_dir ;; > +esac > +fi > + > + > +# If both --with-sysroot and --with-gxx-libcxx-include-dir are passed, we > +# check to see if the latter starts with the former and, upon success, compute > +# gcc_gxx_libcxx_include_dir as relative to the sysroot. > +gcc_gxx_libcxx_include_dir_add_sysroot=0 > + > +if test x${gcc_gxx_libcxx_include_dir} != x; then > + > +$as_echo "#define ENABLE_STDLIB_OPTION 1" >>confdefs.h > + > +else > + $as_echo "#define ENABLE_STDLIB_OPTION 0" >>confdefs.h > + > +fi > +# ??? This logic must match libstdc++-v3/acinclude.m4:GLIBCXX_EXPORT_INSTALL_INFO. > +if test x${gcc_gxx_libcxx_include_dir} = x; then > + if test x${enable_version_specific_runtime_libs} = xyes; then > + gcc_gxx_libcxx_include_dir='${libsubdir}/libc++_include/c++/v1' > + else > + libcxx_incdir='libc++_include/c++/$(version)/v1' > + if test x$host != x$target; then > + libcxx_incdir="$target_alias/$libcxx_incdir" > + fi > + gcc_gxx_libcxx_include_dir="\$(libsubdir)/\$(libsubdir_to_prefix)$libcxx_incdir" > + fi > +elif test "${with_sysroot+set}" = set; then > + gcc_gxx_libcxx_without_sysroot=`expr "${gcc_gxx_libcxx_include_dir}" : "${with_sysroot}"'\(.*\)'` > + if test "${gcc_gxx_libcxx_without_sysroot}"; then > + gcc_gxx_libcxx_include_dir="${gcc_gxx_libcxx_without_sysroot}" > + gcc_gxx_libcxx_include_dir_add_sysroot=1 > + fi > +fi > + > > # Check whether --with-cpp_install_dir was given. > if test "${with_cpp_install_dir+set}" = set; then : > @@ -19186,7 +19237,7 @@ else > lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2 > lt_status=$lt_dlunknown > cat > conftest.$ac_ext <<_LT_EOF > -#line 19189 "configure" > +#line 19240 "configure" > #include "confdefs.h" > > #if HAVE_DLFCN_H > @@ -19292,7 +19343,7 @@ else > lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2 > lt_status=$lt_dlunknown > cat > conftest.$ac_ext <<_LT_EOF > -#line 19295 "configure" > +#line 19346 "configure" > #include "confdefs.h" > > #if HAVE_DLFCN_H > @@ -31175,6 +31226,8 @@ fi > > > > + > + > > > > diff --git a/gcc/configure.ac b/gcc/configure.ac > index 89b9981e872..6fcf154d987 100644 > --- a/gcc/configure.ac > +++ b/gcc/configure.ac > @@ -228,6 +228,48 @@ elif test "${with_sysroot+set}" = set; then > fi > fi > > +# Configuration for an alternate set of C++ headers. > +gcc_gxx_libcxx_include_dir= > +# Specify the alternate g++ header file directory > +AC_ARG_WITH(gxx-libcxx-include-dir, > +[AS_HELP_STRING([--with-gxx-libcxx-include-dir=DIR], > + [specifies directory to find libc++ header files])], > +[case "${withval}" in > +yes) AC_MSG_ERROR(bad value ${withval} given for libc++ include directory) ;; > +no) ;; > +*) gcc_gxx_libcxx_include_dir=$with_gxx_libcxx_include_dir ;; > +esac]) > + > +# If both --with-sysroot and --with-gxx-libcxx-include-dir are passed, we > +# check to see if the latter starts with the former and, upon success, compute > +# gcc_gxx_libcxx_include_dir as relative to the sysroot. > +gcc_gxx_libcxx_include_dir_add_sysroot=0 > + > +if test x${gcc_gxx_libcxx_include_dir} != x; then > + AC_DEFINE(ENABLE_STDLIB_OPTION, 1, > + [Define if the -stdlib= option should be enabled.]) > +else > + AC_DEFINE(ENABLE_STDLIB_OPTION, 0) > +fi > +# ??? This logic must match libstdc++-v3/acinclude.m4:GLIBCXX_EXPORT_INSTALL_INFO. > +if test x${gcc_gxx_libcxx_include_dir} = x; then > + if test x${enable_version_specific_runtime_libs} = xyes; then > + gcc_gxx_libcxx_include_dir='${libsubdir}/libc++_include/c++/v1' > + else > + libcxx_incdir='libc++_include/c++/$(version)/v1' > + if test x$host != x$target; then > + libcxx_incdir="$target_alias/$libcxx_incdir" > + fi > + gcc_gxx_libcxx_include_dir="\$(libsubdir)/\$(libsubdir_to_prefix)$libcxx_incdir" > + fi > +elif test "${with_sysroot+set}" = set; then > + gcc_gxx_libcxx_without_sysroot=`expr "${gcc_gxx_libcxx_include_dir}" : "${with_sysroot}"'\(.*\)'` > + if test "${gcc_gxx_libcxx_without_sysroot}"; then > + gcc_gxx_libcxx_include_dir="${gcc_gxx_libcxx_without_sysroot}" > + gcc_gxx_libcxx_include_dir_add_sysroot=1 > + fi > +fi > + > AC_ARG_WITH(cpp_install_dir, > [AC_HELP_STRING([--with-cpp-install-dir=DIR], > [install the user visible C preprocessor in DIR > @@ -7096,6 +7138,8 @@ AC_SUBST(float_h_file) > AC_SUBST(gcc_config_arguments) > AC_SUBST(gcc_gxx_include_dir) > AC_SUBST(gcc_gxx_include_dir_add_sysroot) > +AC_SUBST(gcc_gxx_libcxx_include_dir) > +AC_SUBST(gcc_gxx_libcxx_include_dir_add_sysroot) > AC_SUBST(host_exeext) > AC_SUBST(host_xm_file_list) > AC_SUBST(host_xm_include_list) > diff --git a/gcc/cp/g++spec.c b/gcc/cp/g++spec.c > index 0f17148ccbd..a8254cd34c9 100644 > --- a/gcc/cp/g++spec.c > +++ b/gcc/cp/g++spec.c > @@ -49,6 +49,34 @@ along with GCC; see the file COPYING3. If not see > #define LIBSTDCXX_STATIC NULL > #endif > > +#ifndef LIBCXX > +#define LIBCXX "c++" > +#endif > +#ifndef LIBCXX_PROFILE > +#define LIBCXX_PROFILE LIBCXX > +#endif > +#ifndef LIBCXX_STATIC > +#define LIBCXX_STATIC NULL > +#endif > + > +#ifndef LIBCXXABI > +#define LIBCXXABI "c++abi" > +#endif > +#ifndef LIBCXXABI_PROFILE > +#define LIBCXXABI_PROFILE LIBCXXABI > +#endif > +#ifndef LIBCXXABI_STATIC > +#define LIBCXXABI_STATIC NULL > +#endif > + > +/* The values used here must match those of the stdlib_kind enumeration > + in c.opt. */ > +enum stdcxxlib_kind > +{ > + USE_LIBSTDCXX = 1, > + USE_LIBCXX = 2 > +}; > + > void > lang_specific_driver (struct cl_decoded_option **in_decoded_options, > unsigned int *in_decoded_options_count, > @@ -59,13 +87,16 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, > /* If nonzero, the user gave us the `-p' or `-pg' flag. */ > int saw_profile_flag = 0; > > - /* What do with libstdc++: > - -1 means we should not link in libstdc++ > - 0 means we should link in libstdc++ if it is needed > - 1 means libstdc++ is needed and should be linked in. > - 2 means libstdc++ is needed and should be linked statically. */ > + /* What action to take for the c++ runtime library: > + -1 means we should not link it in. > + 0 means we should link it if it is needed. > + 1 means it is needed and should be linked in. > + 2 means it is needed but should be linked statically. */ > int library = 0; > > + /* Which c++ runtime library to link. */ > + stdcxxlib_kind which_library = USE_LIBSTDCXX; > + > /* The number of arguments being added to what's in argv, other than > libraries. We use this to track the number of times we've inserted > -xc++/-xnone. */ > @@ -194,6 +225,10 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, > args[i] |= SKIPOPT; > break; > > + case OPT_stdlib_: > + which_library = (stdcxxlib_kind) decoded_options[i].value; > + break; > + > case OPT_SPECIAL_input_file: > { > int len; > @@ -250,6 +285,13 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, > > /* Add one for shared_libgcc or extra static library. */ > num_args = argc + added + need_math + (library > 0) * 4 + 1; > + /* For libc++, on most platforms, the ABI library (usually called libc++abi) > + is provided as a separate DSO, which we must also append. > + However, a platform might have the ability to forward the ABI library > + from libc++, or combine it in some other way; in that case, LIBCXXABI > + should be set to NULL to signal that it need not be appended. */ > + if (which_library == USE_LIBCXX && LIBCXXABI != NULL) > + num_args += 4; > new_decoded_options = XNEWVEC (struct cl_decoded_option, num_args); > > i = 0; > @@ -323,9 +365,25 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, > j++; > } > #endif > - generate_option (OPT_l, > - saw_profile_flag ? LIBSTDCXX_PROFILE : LIBSTDCXX, 1, > - CL_DRIVER, &new_decoded_options[j]); > + if (which_library == USE_LIBCXX) > + { > + generate_option (OPT_l, > + saw_profile_flag ? LIBCXX_PROFILE : LIBCXX, 1, > + CL_DRIVER, &new_decoded_options[j]); > + if (LIBCXXABI != NULL) > + { > + j++; > + added_libraries++; > + generate_option (OPT_l, > + saw_profile_flag ? LIBCXXABI_PROFILE > + : LIBCXXABI, 1, > + CL_DRIVER, &new_decoded_options[j]); > + } > + } > + else > + generate_option (OPT_l, > + saw_profile_flag ? LIBSTDCXX_PROFILE : LIBSTDCXX, 1, > + CL_DRIVER, &new_decoded_options[j]); > added_libraries++; > j++; > /* Add target-dependent static library, if necessary. */ > diff --git a/gcc/cppdefault.c b/gcc/cppdefault.c > index af38cc494ea..eb6f94162cd 100644 > --- a/gcc/cppdefault.c > +++ b/gcc/cppdefault.c > @@ -55,6 +55,11 @@ const struct default_include cpp_include_defaults[] > { GPLUSPLUS_BACKWARD_INCLUDE_DIR, "G++", 1, 1, > GPLUSPLUS_INCLUDE_DIR_ADD_SYSROOT, 0 }, > #endif > +#ifdef GPLUSPLUS_LIBCXX_INCLUDE_DIR > + /* Pick up libc++ include files, if we have -stdlib=libc++. */ > + { GPLUSPLUS_LIBCXX_INCLUDE_DIR, "G++", 2, 1, > + GPLUSPLUS_LIBCXX_INCLUDE_DIR_ADD_SYSROOT, 0 }, > +#endif > #ifdef GCC_INCLUDE_DIR > /* This is the dir for gcc's private headers. */ > { GCC_INCLUDE_DIR, "GCC", 0, 0, 0, 0 }, > diff --git a/gcc/cppdefault.h b/gcc/cppdefault.h > index a681264f75e..35cf24ec29e 100644 > --- a/gcc/cppdefault.h > +++ b/gcc/cppdefault.h > @@ -36,7 +36,12 @@ struct default_include > const char *const fname; /* The name of the directory. */ > const char *const component; /* The component containing the directory > (see update_path in prefix.c) */ > - const char cplusplus; /* Only look here if we're compiling C++. */ > + const char cplusplus; /* When this is non-zero, we should only > + consider this if we're compiling C++. > + When the -stdlib option is configured, this > + may take values greater than 1 to indicate > + which C++ standard library should be > + used. */ > const char cxx_aware; /* Includes in this directory don't need to > be wrapped in extern "C" when compiling > C++. */ > diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi > index d7d354fc4de..3b8b003c51d 100644 > --- a/gcc/doc/invoke.texi > +++ b/gcc/doc/invoke.texi > @@ -242,6 +242,7 @@ in the following sections. > -fext-numeric-literals @gol > -flang-info-include-translate@r{[}=@var{name}@r{]} @gol > -flang-info-include-translate-not @gol > +-stdlib=@var{libstdc++,libc++} @gol > -Wabi-tag -Wcatch-value -Wcatch-value=@var{n} @gol > -Wno-class-conversion -Wclass-memaccess @gol > -Wcomma-subscript -Wconditionally-supported @gol > @@ -3368,6 +3369,15 @@ is used when building the C++ library.) > @opindex flang-info-include-translate-not > Diagnose include translation events. > > +@item -stdlib=@var{libstdc++,libc++} > +@opindex stdlib > +When G++ is configured to support this option, it allows specification of > +alternate C++ runtime libraries. Two options are available: @var{libstdc++} > +(the default, native C++ runtime for G++) and @var{libc++} which is the > +C++ runtime installed on some operating systems (e.g. Darwin versions from > +Darwin11 onwards). The option switches G++ to use the headers from the > +specified library and to emit @code{-lstdc++} or @code{-lc++} respectively, > +when a C++ runtime is required for linking. > @end table > > In addition, these warning options have meanings only for C++ programs: > diff --git a/gcc/incpath.c b/gcc/incpath.c > index 8437939bf1e..14593a1f4c3 100644 > --- a/gcc/incpath.c > +++ b/gcc/incpath.c > @@ -137,7 +137,8 @@ add_standard_paths (const char *sysroot, const char *iprefix, > IPREFIX and search them first. */ > for (p = cpp_include_defaults; p->fname; p++) > { > - if (!p->cplusplus || cxx_stdinc) > + if (p->cplusplus == 0 > + || (cxx_stdinc && (p->cplusplus == flag_stdlib_kind))) > { > /* Should we be translating sysrooted dirs too? Assume > that iprefix and sysroot are mutually exclusive, for > @@ -168,7 +169,8 @@ add_standard_paths (const char *sysroot, const char *iprefix, > > for (p = cpp_include_defaults; p->fname; p++) > { > - if (!p->cplusplus || cxx_stdinc) > + if (p->cplusplus == 0 > + || (cxx_stdinc && (p->cplusplus == flag_stdlib_kind))) > { > char *str; > >
Hi Iain, could you add a note about this change to the gcc-11/changes.html page? There are probably some people who would be interested in this who could use a note about it. Thanks On Tue, Dec 22, 2020 at 3:53 PM Jason Merrill via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > On 12/22/20 3:39 PM, Iain Sandoe wrote: > > Hi Jason, > > > > Jason Merrill <jason@redhat.com> wrote: > > > >> On 11/11/20 3:58 PM, Iain Sandoe wrote: > > > >>> This option allows the user to specify alternate C++ runtime libraries, > >>> for example when a platform uses libc++ as the installed C++ runtime. > >>> It is the same spelling as a clang option that allows that to use libstdc++. > >>> I have had this patch for some time now (more than a year) on Darwin > >>> branches. > >>> > > > >>> + /* Which standard library to link. > >>> + 1 = libstdc++ > >>> + 2 = libc++. */ > >>> + int which_library = 1; > >> > >> Even if this variable is an int, let's introduce an enum for comparing it to specific values. > > > > done - it is also noted that it must track the enum in the opt file. > > > >>> @@ -264,6 +293,8 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, > >>> /* Add one for shared_libgcc or extra static library. */ > >>> num_args = argc + added + need_math + (library > 0) * 4 + 1; > >>> + if (which_library > 1 && LIBCXXABI != NULL) > >>> + num_args += 4; > >> > >> Why does libc++ need more args than libstdc++? Please add a comment. > > > > done (JFTR, it’s because libc++ doesn’t include the abi library for most platforms, so that also has to be > > appended to the link line). > > > >>> +#ifdef GPLUSPLUS_LIBCXX_INCLUDE_DIR > >>> + /* Pick up libc++ include files, if we have -stdlib=libc++. */ > >>> + { GPLUSPLUS_LIBCXX_INCLUDE_DIR, "G++", 2, 1, > >> > >> If you're going to give cplusplus a non-boolean value, the comment in cppdefault.h needs to reflect that. > > > > done. > > > > (re-)tested on x86_64-darwin{11,16,17,19, 20} with the installed libc++ and x86_64-linux-gnu with an > > LLVM-9 build. Bootstrapped and smoke-tested for libc++ (regular testing for libstdc++). > > > > OK for master now? > > OK. > > > thanks > > Iain > > > > ==== revised patch > > > > > > This option allows the user to specifiy alternate C++ runtime libraries, > > for example when a platform uses libc++ as the installed C++ runtime. > > > > We introduce the command line option: -stdlib= which is the user-facing > > mechanism to select the C++ runtime to be used when compiling and linking > > code. This is the same option spelling as that used by clang to allow the > > use of libstdc++. > > > > The availability (and thus function) of the option are a configure-time > > choice using the configuration control: > > --with-gxx-libcxx-include-dir= > > > > Specification of the path for the libc++ headers, enables the -stdlib= > > option (using the path as given), default values are set when the path > > is unconfigured. > > > > If --with-gxx-libcxx-include-dir is given together with --with-sysroot=, > > then we test to see if the include path starts with the sysroot and, if so, > > record the sysroot-relative component as the local path. At runtime, we > > prepend the sysroot that is actually active. > > > > At link time, we use the C++ runtime in force and (if that is libc++) also > > append the libc++abi ABI library. As for other cases, if a target sets the > > name pointer for the ABI library to NULL the G++ driver will omit it from > > the link line. > > > > gcc/ChangeLog: > > > > * configure.ac: Add gxx-libcxx-include-dir handled > > in the same way as the regular cxx header directory. > > * Makefile.in: Regenerated. > > * config.in: Likewise. > > * configure: Likewise. > > * cppdefault.c: Pick up libc++ headers if the option > > is enabled. > > * cppdefault.h (struct default_include): Amend comments > > to reflect the extended use of the cplusplus field. > > * incpath.c (add_standard_paths): Allow for multiple > > c++ header include path variants. > > * doc/invoke.texi: Document the -stdlib= option. > > > > gcc/c-family/ChangeLog: > > > > * c.opt: Add -stdlib= option and enumerations for > > libstdc++ and libc++. > > > > gcc/cp/ChangeLog: > > > > * g++spec.c (LIBCXX, LIBCXX_PROFILE, LIBCXX_STATIC): New. > > (LIBCXXABI, LIBCXXABI_PROFILE, LIBCXXABI_STATIC): New. > > (enum stdcxxlib_kind): New. > > (lang_specific_driver): Allow selection amongst multiple > > c++ runtime libraries. > > --- > > gcc/Makefile.in | 6 ++++ > > gcc/c-family/c.opt | 14 +++++++++ > > gcc/config.in | 6 ++++ > > gcc/configure | 57 ++++++++++++++++++++++++++++++++-- > > gcc/configure.ac | 44 +++++++++++++++++++++++++++ > > gcc/cp/g++spec.c | 74 ++++++++++++++++++++++++++++++++++++++++----- > > gcc/cppdefault.c | 5 +++ > > gcc/cppdefault.h | 7 ++++- > > gcc/doc/invoke.texi | 10 ++++++ > > gcc/incpath.c | 6 ++-- > > 10 files changed, 216 insertions(+), 13 deletions(-) > > > > diff --git a/gcc/Makefile.in b/gcc/Makefile.in > > index 178e4eaa513..6847022f108 100644 > > --- a/gcc/Makefile.in > > +++ b/gcc/Makefile.in > > @@ -679,6 +679,9 @@ build_tooldir = $(exec_prefix)/$(target_noncanonical) > > # Directory in which the compiler finds target-independent g++ includes. > > gcc_gxx_include_dir = @gcc_gxx_include_dir@ > > gcc_gxx_include_dir_add_sysroot = @gcc_gxx_include_dir_add_sysroot@ > > +# Directory in which the compiler finds libc++ includes. > > +gcc_gxx_libcxx_include_dir = @gcc_gxx_libcxx_include_dir@ > > +gcc_gxx_libcxx_include_dir_add_sysroot = @gcc_gxx_libcxx_include_dir_add_sysroot@ > > # Directory to search for site-specific includes. > > local_includedir = $(local_prefix)/include > > includedir = $(prefix)/include > > @@ -1185,6 +1188,7 @@ FLAGS_TO_PASS = \ > > "prefix=$(prefix)" \ > > "local_prefix=$(local_prefix)" \ > > "gxx_include_dir=$(gcc_gxx_include_dir)" \ > > + "gxx_libcxx_include_dir=$(gcc_gxx_libcxx_include_dir)" \ > > "build_tooldir=$(build_tooldir)" \ > > "gcc_tooldir=$(gcc_tooldir)" \ > > "bindir=$(bindir)" \ > > @@ -3004,6 +3008,8 @@ PREPROCESSOR_DEFINES = \ > > -DGPLUSPLUS_INCLUDE_DIR_ADD_SYSROOT=$(gcc_gxx_include_dir_add_sysroot) \ > > -DGPLUSPLUS_TOOL_INCLUDE_DIR=\"$(gcc_gxx_include_dir)/$(target_noncanonical)\" \ > > -DGPLUSPLUS_BACKWARD_INCLUDE_DIR=\"$(gcc_gxx_include_dir)/backward\" \ > > + -DGPLUSPLUS_LIBCXX_INCLUDE_DIR=\"$(gcc_gxx_libcxx_include_dir)\" \ > > + -DGPLUSPLUS_LIBCXX_INCLUDE_DIR_ADD_SYSROOT=$(gcc_gxx_libcxx_include_dir_add_sysroot) \ > > -DLOCAL_INCLUDE_DIR=\"$(local_includedir)\" \ > > -DCROSS_INCLUDE_DIR=\"$(CROSS_SYSTEM_HEADER_DIR)\" \ > > -DTOOL_INCLUDE_DIR=\"$(gcc_tooldir)/include\" \ > > diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt > > index 21d8cd03709..e0c322f61ae 100644 > > --- a/gcc/c-family/c.opt > > +++ b/gcc/c-family/c.opt > > @@ -2356,6 +2356,20 @@ std=iso9899:2018 > > C ObjC Alias(std=c17) > > Conform to the ISO 2017 C standard (published in 2018). > > > > +stdlib= > > +Driver C++ ObjC++ Common Condition(ENABLE_STDLIB_OPTION) Var(flag_stdlib_kind) Joined Enum(stdlib_kind) RejectNegative Init(1) > > +-stdlib=[libstdc++|libc++] The standard library to be used for C++ headers > > +and runtime. > > + > > +Enum > > +Name(stdlib_kind) Type(int) > > + > > +EnumValue > > +Enum(stdlib_kind) String(libstdc++) Value(1) > > + > > +EnumValue > > +Enum(stdlib_kind) String(libc++) Value(2) > > + > > traditional > > Driver > > > > diff --git a/gcc/config.in b/gcc/config.in > > index 216505abd2c..10a13cde586 100644 > > --- a/gcc/config.in > > +++ b/gcc/config.in > > @@ -240,6 +240,12 @@ > > standards-compatible mode on s390 targets. */ > > #undef ENABLE_S390_EXCESS_FLOAT_PRECISION > > > > +/* Define if the -stdlib= option should be enabled. */ > > +#ifndef USED_FOR_TARGET > > +#undef ENABLE_STDLIB_OPTION > > +#endif > > + > > + > > /* Define if you want all operations on trees (the basic data structure of the > > front ends) to be checked for dynamic type safety at runtime. This is > > moderately expensive. */ > > diff --git a/gcc/configure b/gcc/configure > > index fbe92089640..ee9760354b6 100755 > > --- a/gcc/configure > > +++ b/gcc/configure > > @@ -675,6 +675,8 @@ host_xm_defines > > host_xm_include_list > > host_xm_file_list > > host_exeext > > +gcc_gxx_libcxx_include_dir_add_sysroot > > +gcc_gxx_libcxx_include_dir > > gcc_gxx_include_dir_add_sysroot > > gcc_gxx_include_dir > > gcc_config_arguments > > @@ -937,6 +939,7 @@ with_native_system_header_dir > > with_build_sysroot > > with_sysroot > > with_gxx_include_dir > > +with_gxx_libcxx_include_dir > > with_cpp_install_dir > > enable_generated_files_in_srcdir > > with_gnu_ld > > @@ -1801,6 +1804,8 @@ Optional Packages: > > --with-sysroot[=DIR] search for usr/lib, usr/include, et al, within DIR > > --with-gxx-include-dir=DIR > > specifies directory to put g++ header files > > + --with-gxx-libcxx-include-dir=DIR > > + specifies directory to find libc++ header files > > --with-cpp-install-dir=DIR > > install the user visible C preprocessor in DIR > > (relative to PREFIX) as well as PREFIX/bin > > @@ -3731,6 +3736,52 @@ elif test "${with_sysroot+set}" = set; then > > fi > > fi > > > > +# Configuration for an alternate set of C++ headers. > > +gcc_gxx_libcxx_include_dir= > > +# Specify the alternate g++ header file directory > > + > > +# Check whether --with-gxx-libcxx-include-dir was given. > > +if test "${with_gxx_libcxx_include_dir+set}" = set; then : > > + withval=$with_gxx_libcxx_include_dir; case "${withval}" in > > +yes) as_fn_error $? "bad value ${withval} given for libc++ include directory" "$LINENO" 5 ;; > > +no) ;; > > +*) gcc_gxx_libcxx_include_dir=$with_gxx_libcxx_include_dir ;; > > +esac > > +fi > > + > > + > > +# If both --with-sysroot and --with-gxx-libcxx-include-dir are passed, we > > +# check to see if the latter starts with the former and, upon success, compute > > +# gcc_gxx_libcxx_include_dir as relative to the sysroot. > > +gcc_gxx_libcxx_include_dir_add_sysroot=0 > > + > > +if test x${gcc_gxx_libcxx_include_dir} != x; then > > + > > +$as_echo "#define ENABLE_STDLIB_OPTION 1" >>confdefs.h > > + > > +else > > + $as_echo "#define ENABLE_STDLIB_OPTION 0" >>confdefs.h > > + > > +fi > > +# ??? This logic must match libstdc++-v3/acinclude.m4:GLIBCXX_EXPORT_INSTALL_INFO. > > +if test x${gcc_gxx_libcxx_include_dir} = x; then > > + if test x${enable_version_specific_runtime_libs} = xyes; then > > + gcc_gxx_libcxx_include_dir='${libsubdir}/libc++_include/c++/v1' > > + else > > + libcxx_incdir='libc++_include/c++/$(version)/v1' > > + if test x$host != x$target; then > > + libcxx_incdir="$target_alias/$libcxx_incdir" > > + fi > > + gcc_gxx_libcxx_include_dir="\$(libsubdir)/\$(libsubdir_to_prefix)$libcxx_incdir" > > + fi > > +elif test "${with_sysroot+set}" = set; then > > + gcc_gxx_libcxx_without_sysroot=`expr "${gcc_gxx_libcxx_include_dir}" : "${with_sysroot}"'\(.*\)'` > > + if test "${gcc_gxx_libcxx_without_sysroot}"; then > > + gcc_gxx_libcxx_include_dir="${gcc_gxx_libcxx_without_sysroot}" > > + gcc_gxx_libcxx_include_dir_add_sysroot=1 > > + fi > > +fi > > + > > > > # Check whether --with-cpp_install_dir was given. > > if test "${with_cpp_install_dir+set}" = set; then : > > @@ -19186,7 +19237,7 @@ else > > lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2 > > lt_status=$lt_dlunknown > > cat > conftest.$ac_ext <<_LT_EOF > > -#line 19189 "configure" > > +#line 19240 "configure" > > #include "confdefs.h" > > > > #if HAVE_DLFCN_H > > @@ -19292,7 +19343,7 @@ else > > lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2 > > lt_status=$lt_dlunknown > > cat > conftest.$ac_ext <<_LT_EOF > > -#line 19295 "configure" > > +#line 19346 "configure" > > #include "confdefs.h" > > > > #if HAVE_DLFCN_H > > @@ -31175,6 +31226,8 @@ fi > > > > > > > > + > > + > > > > > > > > diff --git a/gcc/configure.ac b/gcc/configure.ac > > index 89b9981e872..6fcf154d987 100644 > > --- a/gcc/configure.ac > > +++ b/gcc/configure.ac > > @@ -228,6 +228,48 @@ elif test "${with_sysroot+set}" = set; then > > fi > > fi > > > > +# Configuration for an alternate set of C++ headers. > > +gcc_gxx_libcxx_include_dir= > > +# Specify the alternate g++ header file directory > > +AC_ARG_WITH(gxx-libcxx-include-dir, > > +[AS_HELP_STRING([--with-gxx-libcxx-include-dir=DIR], > > + [specifies directory to find libc++ header files])], > > +[case "${withval}" in > > +yes) AC_MSG_ERROR(bad value ${withval} given for libc++ include directory) ;; > > +no) ;; > > +*) gcc_gxx_libcxx_include_dir=$with_gxx_libcxx_include_dir ;; > > +esac]) > > + > > +# If both --with-sysroot and --with-gxx-libcxx-include-dir are passed, we > > +# check to see if the latter starts with the former and, upon success, compute > > +# gcc_gxx_libcxx_include_dir as relative to the sysroot. > > +gcc_gxx_libcxx_include_dir_add_sysroot=0 > > + > > +if test x${gcc_gxx_libcxx_include_dir} != x; then > > + AC_DEFINE(ENABLE_STDLIB_OPTION, 1, > > + [Define if the -stdlib= option should be enabled.]) > > +else > > + AC_DEFINE(ENABLE_STDLIB_OPTION, 0) > > +fi > > +# ??? This logic must match libstdc++-v3/acinclude.m4:GLIBCXX_EXPORT_INSTALL_INFO. > > +if test x${gcc_gxx_libcxx_include_dir} = x; then > > + if test x${enable_version_specific_runtime_libs} = xyes; then > > + gcc_gxx_libcxx_include_dir='${libsubdir}/libc++_include/c++/v1' > > + else > > + libcxx_incdir='libc++_include/c++/$(version)/v1' > > + if test x$host != x$target; then > > + libcxx_incdir="$target_alias/$libcxx_incdir" > > + fi > > + gcc_gxx_libcxx_include_dir="\$(libsubdir)/\$(libsubdir_to_prefix)$libcxx_incdir" > > + fi > > +elif test "${with_sysroot+set}" = set; then > > + gcc_gxx_libcxx_without_sysroot=`expr "${gcc_gxx_libcxx_include_dir}" : "${with_sysroot}"'\(.*\)'` > > + if test "${gcc_gxx_libcxx_without_sysroot}"; then > > + gcc_gxx_libcxx_include_dir="${gcc_gxx_libcxx_without_sysroot}" > > + gcc_gxx_libcxx_include_dir_add_sysroot=1 > > + fi > > +fi > > + > > AC_ARG_WITH(cpp_install_dir, > > [AC_HELP_STRING([--with-cpp-install-dir=DIR], > > [install the user visible C preprocessor in DIR > > @@ -7096,6 +7138,8 @@ AC_SUBST(float_h_file) > > AC_SUBST(gcc_config_arguments) > > AC_SUBST(gcc_gxx_include_dir) > > AC_SUBST(gcc_gxx_include_dir_add_sysroot) > > +AC_SUBST(gcc_gxx_libcxx_include_dir) > > +AC_SUBST(gcc_gxx_libcxx_include_dir_add_sysroot) > > AC_SUBST(host_exeext) > > AC_SUBST(host_xm_file_list) > > AC_SUBST(host_xm_include_list) > > diff --git a/gcc/cp/g++spec.c b/gcc/cp/g++spec.c > > index 0f17148ccbd..a8254cd34c9 100644 > > --- a/gcc/cp/g++spec.c > > +++ b/gcc/cp/g++spec.c > > @@ -49,6 +49,34 @@ along with GCC; see the file COPYING3. If not see > > #define LIBSTDCXX_STATIC NULL > > #endif > > > > +#ifndef LIBCXX > > +#define LIBCXX "c++" > > +#endif > > +#ifndef LIBCXX_PROFILE > > +#define LIBCXX_PROFILE LIBCXX > > +#endif > > +#ifndef LIBCXX_STATIC > > +#define LIBCXX_STATIC NULL > > +#endif > > + > > +#ifndef LIBCXXABI > > +#define LIBCXXABI "c++abi" > > +#endif > > +#ifndef LIBCXXABI_PROFILE > > +#define LIBCXXABI_PROFILE LIBCXXABI > > +#endif > > +#ifndef LIBCXXABI_STATIC > > +#define LIBCXXABI_STATIC NULL > > +#endif > > + > > +/* The values used here must match those of the stdlib_kind enumeration > > + in c.opt. */ > > +enum stdcxxlib_kind > > +{ > > + USE_LIBSTDCXX = 1, > > + USE_LIBCXX = 2 > > +}; > > + > > void > > lang_specific_driver (struct cl_decoded_option **in_decoded_options, > > unsigned int *in_decoded_options_count, > > @@ -59,13 +87,16 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, > > /* If nonzero, the user gave us the `-p' or `-pg' flag. */ > > int saw_profile_flag = 0; > > > > - /* What do with libstdc++: > > - -1 means we should not link in libstdc++ > > - 0 means we should link in libstdc++ if it is needed > > - 1 means libstdc++ is needed and should be linked in. > > - 2 means libstdc++ is needed and should be linked statically. */ > > + /* What action to take for the c++ runtime library: > > + -1 means we should not link it in. > > + 0 means we should link it if it is needed. > > + 1 means it is needed and should be linked in. > > + 2 means it is needed but should be linked statically. */ > > int library = 0; > > > > + /* Which c++ runtime library to link. */ > > + stdcxxlib_kind which_library = USE_LIBSTDCXX; > > + > > /* The number of arguments being added to what's in argv, other than > > libraries. We use this to track the number of times we've inserted > > -xc++/-xnone. */ > > @@ -194,6 +225,10 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, > > args[i] |= SKIPOPT; > > break; > > > > + case OPT_stdlib_: > > + which_library = (stdcxxlib_kind) decoded_options[i].value; > > + break; > > + > > case OPT_SPECIAL_input_file: > > { > > int len; > > @@ -250,6 +285,13 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, > > > > /* Add one for shared_libgcc or extra static library. */ > > num_args = argc + added + need_math + (library > 0) * 4 + 1; > > + /* For libc++, on most platforms, the ABI library (usually called libc++abi) > > + is provided as a separate DSO, which we must also append. > > + However, a platform might have the ability to forward the ABI library > > + from libc++, or combine it in some other way; in that case, LIBCXXABI > > + should be set to NULL to signal that it need not be appended. */ > > + if (which_library == USE_LIBCXX && LIBCXXABI != NULL) > > + num_args += 4; > > new_decoded_options = XNEWVEC (struct cl_decoded_option, num_args); > > > > i = 0; > > @@ -323,9 +365,25 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, > > j++; > > } > > #endif > > - generate_option (OPT_l, > > - saw_profile_flag ? LIBSTDCXX_PROFILE : LIBSTDCXX, 1, > > - CL_DRIVER, &new_decoded_options[j]); > > + if (which_library == USE_LIBCXX) > > + { > > + generate_option (OPT_l, > > + saw_profile_flag ? LIBCXX_PROFILE : LIBCXX, 1, > > + CL_DRIVER, &new_decoded_options[j]); > > + if (LIBCXXABI != NULL) > > + { > > + j++; > > + added_libraries++; > > + generate_option (OPT_l, > > + saw_profile_flag ? LIBCXXABI_PROFILE > > + : LIBCXXABI, 1, > > + CL_DRIVER, &new_decoded_options[j]); > > + } > > + } > > + else > > + generate_option (OPT_l, > > + saw_profile_flag ? LIBSTDCXX_PROFILE : LIBSTDCXX, 1, > > + CL_DRIVER, &new_decoded_options[j]); > > added_libraries++; > > j++; > > /* Add target-dependent static library, if necessary. */ > > diff --git a/gcc/cppdefault.c b/gcc/cppdefault.c > > index af38cc494ea..eb6f94162cd 100644 > > --- a/gcc/cppdefault.c > > +++ b/gcc/cppdefault.c > > @@ -55,6 +55,11 @@ const struct default_include cpp_include_defaults[] > > { GPLUSPLUS_BACKWARD_INCLUDE_DIR, "G++", 1, 1, > > GPLUSPLUS_INCLUDE_DIR_ADD_SYSROOT, 0 }, > > #endif > > +#ifdef GPLUSPLUS_LIBCXX_INCLUDE_DIR > > + /* Pick up libc++ include files, if we have -stdlib=libc++. */ > > + { GPLUSPLUS_LIBCXX_INCLUDE_DIR, "G++", 2, 1, > > + GPLUSPLUS_LIBCXX_INCLUDE_DIR_ADD_SYSROOT, 0 }, > > +#endif > > #ifdef GCC_INCLUDE_DIR > > /* This is the dir for gcc's private headers. */ > > { GCC_INCLUDE_DIR, "GCC", 0, 0, 0, 0 }, > > diff --git a/gcc/cppdefault.h b/gcc/cppdefault.h > > index a681264f75e..35cf24ec29e 100644 > > --- a/gcc/cppdefault.h > > +++ b/gcc/cppdefault.h > > @@ -36,7 +36,12 @@ struct default_include > > const char *const fname; /* The name of the directory. */ > > const char *const component; /* The component containing the directory > > (see update_path in prefix.c) */ > > - const char cplusplus; /* Only look here if we're compiling C++. */ > > + const char cplusplus; /* When this is non-zero, we should only > > + consider this if we're compiling C++. > > + When the -stdlib option is configured, this > > + may take values greater than 1 to indicate > > + which C++ standard library should be > > + used. */ > > const char cxx_aware; /* Includes in this directory don't need to > > be wrapped in extern "C" when compiling > > C++. */ > > diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi > > index d7d354fc4de..3b8b003c51d 100644 > > --- a/gcc/doc/invoke.texi > > +++ b/gcc/doc/invoke.texi > > @@ -242,6 +242,7 @@ in the following sections. > > -fext-numeric-literals @gol > > -flang-info-include-translate@r{[}=@var{name}@r{]} @gol > > -flang-info-include-translate-not @gol > > +-stdlib=@var{libstdc++,libc++} @gol > > -Wabi-tag -Wcatch-value -Wcatch-value=@var{n} @gol > > -Wno-class-conversion -Wclass-memaccess @gol > > -Wcomma-subscript -Wconditionally-supported @gol > > @@ -3368,6 +3369,15 @@ is used when building the C++ library.) > > @opindex flang-info-include-translate-not > > Diagnose include translation events. > > > > +@item -stdlib=@var{libstdc++,libc++} > > +@opindex stdlib > > +When G++ is configured to support this option, it allows specification of > > +alternate C++ runtime libraries. Two options are available: @var{libstdc++} > > +(the default, native C++ runtime for G++) and @var{libc++} which is the > > +C++ runtime installed on some operating systems (e.g. Darwin versions from > > +Darwin11 onwards). The option switches G++ to use the headers from the > > +specified library and to emit @code{-lstdc++} or @code{-lc++} respectively, > > +when a C++ runtime is required for linking. > > @end table > > > > In addition, these warning options have meanings only for C++ programs: > > diff --git a/gcc/incpath.c b/gcc/incpath.c > > index 8437939bf1e..14593a1f4c3 100644 > > --- a/gcc/incpath.c > > +++ b/gcc/incpath.c > > @@ -137,7 +137,8 @@ add_standard_paths (const char *sysroot, const char *iprefix, > > IPREFIX and search them first. */ > > for (p = cpp_include_defaults; p->fname; p++) > > { > > - if (!p->cplusplus || cxx_stdinc) > > + if (p->cplusplus == 0 > > + || (cxx_stdinc && (p->cplusplus == flag_stdlib_kind))) > > { > > /* Should we be translating sysrooted dirs too? Assume > > that iprefix and sysroot are mutually exclusive, for > > @@ -168,7 +169,8 @@ add_standard_paths (const char *sysroot, const char *iprefix, > > > > for (p = cpp_include_defaults; p->fname; p++) > > { > > - if (!p->cplusplus || cxx_stdinc) > > + if (p->cplusplus == 0 > > + || (cxx_stdinc && (p->cplusplus == flag_stdlib_kind))) > > { > > char *str; > > > > >
diff --git a/gcc/Makefile.in b/gcc/Makefile.in index 178e4eaa513..6847022f108 100644 --- a/gcc/Makefile.in +++ b/gcc/Makefile.in @@ -679,6 +679,9 @@ build_tooldir = $(exec_prefix)/$(target_noncanonical) # Directory in which the compiler finds target-independent g++ includes. gcc_gxx_include_dir = @gcc_gxx_include_dir@ gcc_gxx_include_dir_add_sysroot = @gcc_gxx_include_dir_add_sysroot@ +# Directory in which the compiler finds libc++ includes. +gcc_gxx_libcxx_include_dir = @gcc_gxx_libcxx_include_dir@ +gcc_gxx_libcxx_include_dir_add_sysroot = @gcc_gxx_libcxx_include_dir_add_sysroot@ # Directory to search for site-specific includes. local_includedir = $(local_prefix)/include includedir = $(prefix)/include @@ -1185,6 +1188,7 @@ FLAGS_TO_PASS = \ "prefix=$(prefix)" \ "local_prefix=$(local_prefix)" \ "gxx_include_dir=$(gcc_gxx_include_dir)" \ + "gxx_libcxx_include_dir=$(gcc_gxx_libcxx_include_dir)" \ "build_tooldir=$(build_tooldir)" \ "gcc_tooldir=$(gcc_tooldir)" \ "bindir=$(bindir)" \ @@ -3004,6 +3008,8 @@ PREPROCESSOR_DEFINES = \ -DGPLUSPLUS_INCLUDE_DIR_ADD_SYSROOT=$(gcc_gxx_include_dir_add_sysroot) \ -DGPLUSPLUS_TOOL_INCLUDE_DIR=\"$(gcc_gxx_include_dir)/$(target_noncanonical)\" \ -DGPLUSPLUS_BACKWARD_INCLUDE_DIR=\"$(gcc_gxx_include_dir)/backward\" \ + -DGPLUSPLUS_LIBCXX_INCLUDE_DIR=\"$(gcc_gxx_libcxx_include_dir)\" \ + -DGPLUSPLUS_LIBCXX_INCLUDE_DIR_ADD_SYSROOT=$(gcc_gxx_libcxx_include_dir_add_sysroot) \ -DLOCAL_INCLUDE_DIR=\"$(local_includedir)\" \ -DCROSS_INCLUDE_DIR=\"$(CROSS_SYSTEM_HEADER_DIR)\" \ -DTOOL_INCLUDE_DIR=\"$(gcc_tooldir)/include\" \ diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt index 21d8cd03709..e0c322f61ae 100644 --- a/gcc/c-family/c.opt +++ b/gcc/c-family/c.opt @@ -2356,6 +2356,20 @@ std=iso9899:2018 C ObjC Alias(std=c17) Conform to the ISO 2017 C standard (published in 2018). +stdlib= +Driver C++ ObjC++ Common Condition(ENABLE_STDLIB_OPTION) Var(flag_stdlib_kind) Joined Enum(stdlib_kind) RejectNegative Init(1) +-stdlib=[libstdc++|libc++] The standard library to be used for C++ headers +and runtime. + +Enum +Name(stdlib_kind) Type(int) + +EnumValue +Enum(stdlib_kind) String(libstdc++) Value(1) + +EnumValue +Enum(stdlib_kind) String(libc++) Value(2) + traditional Driver diff --git a/gcc/config.in b/gcc/config.in index 216505abd2c..10a13cde586 100644 --- a/gcc/config.in +++ b/gcc/config.in @@ -240,6 +240,12 @@ standards-compatible mode on s390 targets. */ #undef ENABLE_S390_EXCESS_FLOAT_PRECISION +/* Define if the -stdlib= option should be enabled. */ +#ifndef USED_FOR_TARGET +#undef ENABLE_STDLIB_OPTION +#endif + + /* Define if you want all operations on trees (the basic data structure of the front ends) to be checked for dynamic type safety at runtime. This is moderately expensive. */ diff --git a/gcc/configure b/gcc/configure index fbe92089640..ee9760354b6 100755 --- a/gcc/configure +++ b/gcc/configure @@ -675,6 +675,8 @@ host_xm_defines host_xm_include_list host_xm_file_list host_exeext +gcc_gxx_libcxx_include_dir_add_sysroot +gcc_gxx_libcxx_include_dir gcc_gxx_include_dir_add_sysroot gcc_gxx_include_dir gcc_config_arguments @@ -937,6 +939,7 @@ with_native_system_header_dir with_build_sysroot with_sysroot with_gxx_include_dir +with_gxx_libcxx_include_dir with_cpp_install_dir enable_generated_files_in_srcdir with_gnu_ld @@ -1801,6 +1804,8 @@ Optional Packages: --with-sysroot[=DIR] search for usr/lib, usr/include, et al, within DIR --with-gxx-include-dir=DIR specifies directory to put g++ header files + --with-gxx-libcxx-include-dir=DIR + specifies directory to find libc++ header files --with-cpp-install-dir=DIR install the user visible C preprocessor in DIR (relative to PREFIX) as well as PREFIX/bin @@ -3731,6 +3736,52 @@ elif test "${with_sysroot+set}" = set; then fi fi +# Configuration for an alternate set of C++ headers. +gcc_gxx_libcxx_include_dir= +# Specify the alternate g++ header file directory + +# Check whether --with-gxx-libcxx-include-dir was given. +if test "${with_gxx_libcxx_include_dir+set}" = set; then : + withval=$with_gxx_libcxx_include_dir; case "${withval}" in +yes) as_fn_error $? "bad value ${withval} given for libc++ include directory" "$LINENO" 5 ;; +no) ;; +*) gcc_gxx_libcxx_include_dir=$with_gxx_libcxx_include_dir ;; +esac +fi + + +# If both --with-sysroot and --with-gxx-libcxx-include-dir are passed, we +# check to see if the latter starts with the former and, upon success, compute +# gcc_gxx_libcxx_include_dir as relative to the sysroot. +gcc_gxx_libcxx_include_dir_add_sysroot=0 + +if test x${gcc_gxx_libcxx_include_dir} != x; then + +$as_echo "#define ENABLE_STDLIB_OPTION 1" >>confdefs.h + +else + $as_echo "#define ENABLE_STDLIB_OPTION 0" >>confdefs.h + +fi +# ??? This logic must match libstdc++-v3/acinclude.m4:GLIBCXX_EXPORT_INSTALL_INFO. +if test x${gcc_gxx_libcxx_include_dir} = x; then + if test x${enable_version_specific_runtime_libs} = xyes; then + gcc_gxx_libcxx_include_dir='${libsubdir}/libc++_include/c++/v1' + else + libcxx_incdir='libc++_include/c++/$(version)/v1' + if test x$host != x$target; then + libcxx_incdir="$target_alias/$libcxx_incdir" + fi + gcc_gxx_libcxx_include_dir="\$(libsubdir)/\$(libsubdir_to_prefix)$libcxx_incdir" + fi +elif test "${with_sysroot+set}" = set; then + gcc_gxx_libcxx_without_sysroot=`expr "${gcc_gxx_libcxx_include_dir}" : "${with_sysroot}"'\(.*\)'` + if test "${gcc_gxx_libcxx_without_sysroot}"; then + gcc_gxx_libcxx_include_dir="${gcc_gxx_libcxx_without_sysroot}" + gcc_gxx_libcxx_include_dir_add_sysroot=1 + fi +fi + # Check whether --with-cpp_install_dir was given. if test "${with_cpp_install_dir+set}" = set; then : @@ -19186,7 +19237,7 @@ else lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2 lt_status=$lt_dlunknown cat > conftest.$ac_ext <<_LT_EOF -#line 19189 "configure" +#line 19240 "configure" #include "confdefs.h" #if HAVE_DLFCN_H @@ -19292,7 +19343,7 @@ else lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2 lt_status=$lt_dlunknown cat > conftest.$ac_ext <<_LT_EOF -#line 19295 "configure" +#line 19346 "configure" #include "confdefs.h" #if HAVE_DLFCN_H @@ -31175,6 +31226,8 @@ fi + + diff --git a/gcc/configure.ac b/gcc/configure.ac index 89b9981e872..6fcf154d987 100644 --- a/gcc/configure.ac +++ b/gcc/configure.ac @@ -228,6 +228,48 @@ elif test "${with_sysroot+set}" = set; then fi fi +# Configuration for an alternate set of C++ headers. +gcc_gxx_libcxx_include_dir= +# Specify the alternate g++ header file directory +AC_ARG_WITH(gxx-libcxx-include-dir, +[AS_HELP_STRING([--with-gxx-libcxx-include-dir=DIR], + [specifies directory to find libc++ header files])], +[case "${withval}" in +yes) AC_MSG_ERROR(bad value ${withval} given for libc++ include directory) ;; +no) ;; +*) gcc_gxx_libcxx_include_dir=$with_gxx_libcxx_include_dir ;; +esac]) + +# If both --with-sysroot and --with-gxx-libcxx-include-dir are passed, we +# check to see if the latter starts with the former and, upon success, compute +# gcc_gxx_libcxx_include_dir as relative to the sysroot. +gcc_gxx_libcxx_include_dir_add_sysroot=0 + +if test x${gcc_gxx_libcxx_include_dir} != x; then + AC_DEFINE(ENABLE_STDLIB_OPTION, 1, + [Define if the -stdlib= option should be enabled.]) +else + AC_DEFINE(ENABLE_STDLIB_OPTION, 0) +fi +# ??? This logic must match libstdc++-v3/acinclude.m4:GLIBCXX_EXPORT_INSTALL_INFO. +if test x${gcc_gxx_libcxx_include_dir} = x; then + if test x${enable_version_specific_runtime_libs} = xyes; then + gcc_gxx_libcxx_include_dir='${libsubdir}/libc++_include/c++/v1' + else + libcxx_incdir='libc++_include/c++/$(version)/v1' + if test x$host != x$target; then + libcxx_incdir="$target_alias/$libcxx_incdir" + fi + gcc_gxx_libcxx_include_dir="\$(libsubdir)/\$(libsubdir_to_prefix)$libcxx_incdir" + fi +elif test "${with_sysroot+set}" = set; then + gcc_gxx_libcxx_without_sysroot=`expr "${gcc_gxx_libcxx_include_dir}" : "${with_sysroot}"'\(.*\)'` + if test "${gcc_gxx_libcxx_without_sysroot}"; then + gcc_gxx_libcxx_include_dir="${gcc_gxx_libcxx_without_sysroot}" + gcc_gxx_libcxx_include_dir_add_sysroot=1 + fi +fi + AC_ARG_WITH(cpp_install_dir, [AC_HELP_STRING([--with-cpp-install-dir=DIR], [install the user visible C preprocessor in DIR @@ -7096,6 +7138,8 @@ AC_SUBST(float_h_file) AC_SUBST(gcc_config_arguments) AC_SUBST(gcc_gxx_include_dir) AC_SUBST(gcc_gxx_include_dir_add_sysroot) +AC_SUBST(gcc_gxx_libcxx_include_dir) +AC_SUBST(gcc_gxx_libcxx_include_dir_add_sysroot) AC_SUBST(host_exeext) AC_SUBST(host_xm_file_list) AC_SUBST(host_xm_include_list) diff --git a/gcc/cp/g++spec.c b/gcc/cp/g++spec.c index 0f17148ccbd..a8254cd34c9 100644 --- a/gcc/cp/g++spec.c +++ b/gcc/cp/g++spec.c @@ -49,6 +49,34 @@ along with GCC; see the file COPYING3. If not see #define LIBSTDCXX_STATIC NULL #endif +#ifndef LIBCXX +#define LIBCXX "c++" +#endif +#ifndef LIBCXX_PROFILE +#define LIBCXX_PROFILE LIBCXX +#endif +#ifndef LIBCXX_STATIC +#define LIBCXX_STATIC NULL +#endif + +#ifndef LIBCXXABI +#define LIBCXXABI "c++abi" +#endif +#ifndef LIBCXXABI_PROFILE +#define LIBCXXABI_PROFILE LIBCXXABI +#endif +#ifndef LIBCXXABI_STATIC +#define LIBCXXABI_STATIC NULL +#endif + +/* The values used here must match those of the stdlib_kind enumeration + in c.opt. */ +enum stdcxxlib_kind +{ + USE_LIBSTDCXX = 1, + USE_LIBCXX = 2 +}; + void lang_specific_driver (struct cl_decoded_option **in_decoded_options, unsigned int *in_decoded_options_count, @@ -59,13 +87,16 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, /* If nonzero, the user gave us the `-p' or `-pg' flag. */ int saw_profile_flag = 0; - /* What do with libstdc++: - -1 means we should not link in libstdc++ - 0 means we should link in libstdc++ if it is needed - 1 means libstdc++ is needed and should be linked in. - 2 means libstdc++ is needed and should be linked statically. */ + /* What action to take for the c++ runtime library: + -1 means we should not link it in. + 0 means we should link it if it is needed. + 1 means it is needed and should be linked in. + 2 means it is needed but should be linked statically. */ int library = 0; + /* Which c++ runtime library to link. */ + stdcxxlib_kind which_library = USE_LIBSTDCXX; + /* The number of arguments being added to what's in argv, other than libraries. We use this to track the number of times we've inserted -xc++/-xnone. */ @@ -194,6 +225,10 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, args[i] |= SKIPOPT; break; + case OPT_stdlib_: + which_library = (stdcxxlib_kind) decoded_options[i].value; + break; + case OPT_SPECIAL_input_file: { int len; @@ -250,6 +285,13 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, /* Add one for shared_libgcc or extra static library. */ num_args = argc + added + need_math + (library > 0) * 4 + 1; + /* For libc++, on most platforms, the ABI library (usually called libc++abi) + is provided as a separate DSO, which we must also append. + However, a platform might have the ability to forward the ABI library + from libc++, or combine it in some other way; in that case, LIBCXXABI + should be set to NULL to signal that it need not be appended. */ + if (which_library == USE_LIBCXX && LIBCXXABI != NULL) + num_args += 4; new_decoded_options = XNEWVEC (struct cl_decoded_option, num_args); i = 0; @@ -323,9 +365,25 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options, j++; } #endif - generate_option (OPT_l, - saw_profile_flag ? LIBSTDCXX_PROFILE : LIBSTDCXX, 1, - CL_DRIVER, &new_decoded_options[j]); + if (which_library == USE_LIBCXX) + { + generate_option (OPT_l, + saw_profile_flag ? LIBCXX_PROFILE : LIBCXX, 1, + CL_DRIVER, &new_decoded_options[j]); + if (LIBCXXABI != NULL) + { + j++; + added_libraries++; + generate_option (OPT_l, + saw_profile_flag ? LIBCXXABI_PROFILE + : LIBCXXABI, 1, + CL_DRIVER, &new_decoded_options[j]); + } + } + else + generate_option (OPT_l, + saw_profile_flag ? LIBSTDCXX_PROFILE : LIBSTDCXX, 1, + CL_DRIVER, &new_decoded_options[j]); added_libraries++; j++; /* Add target-dependent static library, if necessary. */ diff --git a/gcc/cppdefault.c b/gcc/cppdefault.c index af38cc494ea..eb6f94162cd 100644 --- a/gcc/cppdefault.c +++ b/gcc/cppdefault.c @@ -55,6 +55,11 @@ const struct default_include cpp_include_defaults[] { GPLUSPLUS_BACKWARD_INCLUDE_DIR, "G++", 1, 1, GPLUSPLUS_INCLUDE_DIR_ADD_SYSROOT, 0 }, #endif +#ifdef GPLUSPLUS_LIBCXX_INCLUDE_DIR + /* Pick up libc++ include files, if we have -stdlib=libc++. */ + { GPLUSPLUS_LIBCXX_INCLUDE_DIR, "G++", 2, 1, + GPLUSPLUS_LIBCXX_INCLUDE_DIR_ADD_SYSROOT, 0 }, +#endif #ifdef GCC_INCLUDE_DIR /* This is the dir for gcc's private headers. */ { GCC_INCLUDE_DIR, "GCC", 0, 0, 0, 0 }, diff --git a/gcc/cppdefault.h b/gcc/cppdefault.h index a681264f75e..35cf24ec29e 100644 --- a/gcc/cppdefault.h +++ b/gcc/cppdefault.h @@ -36,7 +36,12 @@ struct default_include const char *const fname; /* The name of the directory. */ const char *const component; /* The component containing the directory (see update_path in prefix.c) */ - const char cplusplus; /* Only look here if we're compiling C++. */ + const char cplusplus; /* When this is non-zero, we should only + consider this if we're compiling C++. + When the -stdlib option is configured, this + may take values greater than 1 to indicate + which C++ standard library should be + used. */ const char cxx_aware; /* Includes in this directory don't need to be wrapped in extern "C" when compiling C++. */ diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index d7d354fc4de..3b8b003c51d 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -242,6 +242,7 @@ in the following sections. -fext-numeric-literals @gol -flang-info-include-translate@r{[}=@var{name}@r{]} @gol -flang-info-include-translate-not @gol +-stdlib=@var{libstdc++,libc++} @gol -Wabi-tag -Wcatch-value -Wcatch-value=@var{n} @gol -Wno-class-conversion -Wclass-memaccess @gol -Wcomma-subscript -Wconditionally-supported @gol @@ -3368,6 +3369,15 @@ is used when building the C++ library.) @opindex flang-info-include-translate-not Diagnose include translation events. +@item -stdlib=@var{libstdc++,libc++} +@opindex stdlib +When G++ is configured to support this option, it allows specification of +alternate C++ runtime libraries. Two options are available: @var{libstdc++} +(the default, native C++ runtime for G++) and @var{libc++} which is the +C++ runtime installed on some operating systems (e.g. Darwin versions from +Darwin11 onwards). The option switches G++ to use the headers from the +specified library and to emit @code{-lstdc++} or @code{-lc++} respectively, +when a C++ runtime is required for linking. @end table In addition, these warning options have meanings only for C++ programs: diff --git a/gcc/incpath.c b/gcc/incpath.c index 8437939bf1e..14593a1f4c3 100644 --- a/gcc/incpath.c +++ b/gcc/incpath.c @@ -137,7 +137,8 @@ add_standard_paths (const char *sysroot, const char *iprefix, IPREFIX and search them first. */ for (p = cpp_include_defaults; p->fname; p++) { - if (!p->cplusplus || cxx_stdinc) + if (p->cplusplus == 0 + || (cxx_stdinc && (p->cplusplus == flag_stdlib_kind))) { /* Should we be translating sysrooted dirs too? Assume that iprefix and sysroot are mutually exclusive, for @@ -168,7 +169,8 @@ add_standard_paths (const char *sysroot, const char *iprefix, for (p = cpp_include_defaults; p->fname; p++) { - if (!p->cplusplus || cxx_stdinc) + if (p->cplusplus == 0 + || (cxx_stdinc && (p->cplusplus == flag_stdlib_kind))) { char *str;