| Message ID | 4DFBE75A.6010405@codesourcery.com |
|---|---|
| State | New |
| Headers | show |
Ping? http://gcc.gnu.org/ml/gcc-patches/2011-06/msg01368.html > We had a bug report from a customer that the linker was ignoring the > --demangle and --no-demangle options when generating map files. > Moreover, it was failing in a host-dependent way; on Windows hosts, > it was always emitting demangled names in the map file, while on > Linux hosts, it never did. Moreover, on Windows hosts it also > ignored the setting of the COLLECT_NO_DEMANGLE environment variable. > > This turns out to be a problem in collect2, or actually, three > problems: > > (1) By default, collect2 is configured to filter out --demangle and > --no-demangle from the linker options, and it tries to do demangling > on symbol names in stdout and stderr itself instead. But, it is too > stupid to know about the map file. > > (2) Collect2 is trying to set COLLECT_NO_DEMANGLE to disable > demangling in ld, but in a nonportable way that causes it to be > always unset instead on Windows. > > (3) If you configure with --with-demangler-in-ld to try to disable > the collect2 demangling, there's another bug that causes it to ignore > any explicit --demangle or --no-demangle options and only pay > attention to whether or not COLLECT_NO_DEMANGLE is set. > > The attached patch addresses all three problems: > > (1) I've flipped the default to --with-demangler-in-ld=yes. Note > that configure.ac already takes care not to let this percolate > through to collect2 without verifying that the linker is GNU ld and > that it is a version that supports --demangle. Perhaps back in 2004 > when this option was first added, the ld demangling support was > deemed too experimental to make it the default, but that's surely not > the case any more. Also, since this has been broken since 2004, I'm > not sure there's much reason to be concerned with backwards > compatibility, here.... > > (2) I fixed the COLLECT_NO_DEMANGLE environment variable setting > recipe. > > (3) I simplified the argument processing for --demangle and > --no-demangle to pass them straight through to the linker when > HAVE_LD_DEMANGLE is defined. > > OK to commit? > > -Sandra > > 2011-06-17 Sandra Loosemore <sandra@codesourcery.com> > > gcc/ > * configure.ac (demangler_in_ld): Default to yes. > * configure: Regenerated. > * collect2.c (main): When HAVE_LD_DEMANGLE is defined, don't > mess with COLLECT_NO_DEMANGLE, and just pass --demangle and > --no-demangle options straight through to ld. When > HAVE_LD_DEMANGLE is not defined, set COLLECT_NO_DEMANGLE in a > way that has the intended effect on Windows. > >
Ping? http://gcc.gnu.org/ml/gcc-patches/2011-06/msg01368.html > We had a bug report from a customer that the linker was ignoring the > --demangle and --no-demangle options when generating map files. > Moreover, it was failing in a host-dependent way; on Windows hosts, > it was always emitting demangled names in the map file, while on > Linux hosts, it never did. Moreover, on Windows hosts it also > ignored the setting of the COLLECT_NO_DEMANGLE environment variable. > > This turns out to be a problem in collect2, or actually, three > problems: > > (1) By default, collect2 is configured to filter out --demangle and > --no-demangle from the linker options, and it tries to do demangling > on symbol names in stdout and stderr itself instead. But, it is too > stupid to know about the map file. > > (2) Collect2 is trying to set COLLECT_NO_DEMANGLE to disable > demangling in ld, but in a nonportable way that causes it to be > always unset instead on Windows. > > (3) If you configure with --with-demangler-in-ld to try to disable > the collect2 demangling, there's another bug that causes it to ignore > any explicit --demangle or --no-demangle options and only pay > attention to whether or not COLLECT_NO_DEMANGLE is set. > > The attached patch addresses all three problems: > > (1) I've flipped the default to --with-demangler-in-ld=yes. Note > that configure.ac already takes care not to let this percolate > through to collect2 without verifying that the linker is GNU ld and > that it is a version that supports --demangle. Perhaps back in 2004 > when this option was first added, the ld demangling support was > deemed too experimental to make it the default, but that's surely not > the case any more. Also, since this has been broken since 2004, I'm > not sure there's much reason to be concerned with backwards > compatibility, here.... > > (2) I fixed the COLLECT_NO_DEMANGLE environment variable setting > recipe. > > (3) I simplified the argument processing for --demangle and > --no-demangle to pass them straight through to the linker when > HAVE_LD_DEMANGLE is defined. > > OK to commit? > > -Sandra > > 2011-06-17 Sandra Loosemore <sandra@codesourcery.com> > > gcc/ > * configure.ac (demangler_in_ld): Default to yes. > * configure: Regenerated. > * collect2.c (main): When HAVE_LD_DEMANGLE is defined, don't > mess with COLLECT_NO_DEMANGLE, and just pass --demangle and > --no-demangle options straight through to ld. When > HAVE_LD_DEMANGLE is not defined, set COLLECT_NO_DEMANGLE in a > way that has the intended effect on Windows. > >
OK in the absence of middle-end or build-system maintainer objections within 72 hours.
On Mon, Jul 11, 2011 at 10:45 AM, Sandra Loosemore <sandra@codesourcery.com> wrote: > Ping? > > http://gcc.gnu.org/ml/gcc-patches/2011-06/msg01368.html > >> We had a bug report from a customer that the linker was ignoring the >> --demangle and --no-demangle options when generating map files. >> Moreover, it was failing in a host-dependent way; on Windows hosts, >> it was always emitting demangled names in the map file, while on >> Linux hosts, it never did. Moreover, on Windows hosts it also >> ignored the setting of the COLLECT_NO_DEMANGLE environment variable. >> >> This turns out to be a problem in collect2, or actually, three >> problems: >> >> (1) By default, collect2 is configured to filter out --demangle and >> --no-demangle from the linker options, and it tries to do demangling >> on symbol names in stdout and stderr itself instead. But, it is too >> stupid to know about the map file. >> >> (2) Collect2 is trying to set COLLECT_NO_DEMANGLE to disable >> demangling in ld, but in a nonportable way that causes it to be >> always unset instead on Windows. >> >> (3) If you configure with --with-demangler-in-ld to try to disable >> the collect2 demangling, there's another bug that causes it to ignore >> any explicit --demangle or --no-demangle options and only pay >> attention to whether or not COLLECT_NO_DEMANGLE is set. >> >> The attached patch addresses all three problems: >> >> (1) I've flipped the default to --with-demangler-in-ld=yes. Note >> that configure.ac already takes care not to let this percolate >> through to collect2 without verifying that the linker is GNU ld and >> that it is a version that supports --demangle. Perhaps back in 2004 >> when this option was first added, the ld demangling support was >> deemed too experimental to make it the default, but that's surely not >> the case any more. Also, since this has been broken since 2004, I'm >> not sure there's much reason to be concerned with backwards >> compatibility, here.... >> >> (2) I fixed the COLLECT_NO_DEMANGLE environment variable setting >> recipe. >> >> (3) I simplified the argument processing for --demangle and >> --no-demangle to pass them straight through to the linker when >> HAVE_LD_DEMANGLE is defined. >> >> OK to commit? >> >> -Sandra >> >> 2011-06-17 Sandra Loosemore <sandra@codesourcery.com> >> >> gcc/ >> * configure.ac (demangler_in_ld): Default to yes. >> * configure: Regenerated. >> * collect2.c (main): When HAVE_LD_DEMANGLE is defined, don't >> mess with COLLECT_NO_DEMANGLE, and just pass --demangle and >> --no-demangle options straight through to ld. When >> HAVE_LD_DEMANGLE is not defined, set COLLECT_NO_DEMANGLE in a >> way that has the intended effect on Windows. It caused: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49835
Index: configure.ac =================================================================== --- configure.ac (revision 175123) +++ configure.ac (working copy) @@ -222,7 +222,7 @@ fi AC_ARG_WITH(demangler-in-ld, [AS_HELP_STRING([--with-demangler-in-ld], [try to use demangler in GNU ld])], demangler_in_ld="$with_demangler_in_ld", -demangler_in_ld=no) +demangler_in_ld=yes) # ---------------------- # Find default assembler Index: configure =================================================================== --- configure (revision 175123) +++ configure (working copy) @@ -3413,7 +3413,7 @@ fi if test "${with_demangler_in_ld+set}" = set; then : withval=$with_demangler_in_ld; demangler_in_ld="$with_demangler_in_ld" else - demangler_in_ld=no + demangler_in_ld=yes fi Index: collect2.c =================================================================== --- collect2.c (revision 175123) +++ collect2.c (working copy) @@ -1112,10 +1112,12 @@ main (int argc, char **argv) num_c_args = argc + 9; +#ifndef HAVE_LD_DEMANGLE no_demangle = !! getenv ("COLLECT_NO_DEMANGLE"); /* Suppress demangling by the real linker, which may be broken. */ - putenv (xstrdup ("COLLECT_NO_DEMANGLE=")); + putenv (xstrdup ("COLLECT_NO_DEMANGLE=1")); +#endif #if defined (COLLECT2_HOST_INITIALIZATION) /* Perform system dependent initialization, if necessary. */ @@ -1405,12 +1407,6 @@ main (int argc, char **argv) /* After the first file, put in the c++ rt0. */ first_file = 1; -#ifdef HAVE_LD_DEMANGLE - if (!demangle_flag && !no_demangle) - demangle_flag = "--demangle"; - if (demangle_flag) - *ld1++ = *ld2++ = demangle_flag; -#endif while ((arg = *++argv) != (char *) 0) { *ld1++ = *ld2++ = arg; @@ -1514,16 +1510,16 @@ main (int argc, char **argv) case '-': if (strcmp (arg, "--no-demangle") == 0) { - demangle_flag = arg; +#ifndef HAVE_LD_DEMANGLE no_demangle = 1; ld1--; ld2--; +#endif } else if (strncmp (arg, "--demangle", 10) == 0) { - demangle_flag = arg; - no_demangle = 0; #ifndef HAVE_LD_DEMANGLE + no_demangle = 0; if (arg[10] == '=') { enum demangling_styles style @@ -1533,9 +1529,9 @@ main (int argc, char **argv) else current_demangling_style = style; } -#endif ld1--; ld2--; +#endif } else if (strncmp (arg, "--sysroot=", 10) == 0) target_system_root = arg + 10;