| Message ID | 20201204230615.2392-2-dbuono@linux.vnet.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add support for Control-Flow Integrity | expand |
On 05/12/2020 00.06, Daniele Buono wrote: > This patch allows to compile QEMU with link-time optimization (LTO). > Compilation with LTO is handled directly by meson. This patch only > adds the option in configure and forwards the request to meson > > Tested with all major versions of clang from 6 to 12 > > Signed-off-by: Daniele Buono <dbuono@linux.vnet.ibm.com> > --- > configure | 7 +++++++ > meson.build | 1 + > 2 files changed, 8 insertions(+) > > diff --git a/configure b/configure > index 18c26e0389..fee118518b 100755 > --- a/configure > +++ b/configure > @@ -242,6 +242,7 @@ host_cc="cc" > audio_win_int="" > libs_qga="" > debug_info="yes" > +lto="false" > stack_protector="" > safe_stack="" > use_containers="yes" > @@ -1167,6 +1168,10 @@ for opt do > ;; > --disable-werror) werror="no" > ;; > + --enable-lto) lto="true" > + ;; > + --disable-lto) lto="false" > + ;; > --enable-stack-protector) stack_protector="yes" > ;; > --disable-stack-protector) stack_protector="no" > @@ -1751,6 +1756,7 @@ disabled with --disable-FEATURE, default is enabled if available: > module-upgrades try to load modules from alternate paths for upgrades > debug-tcg TCG debugging (default is disabled) > debug-info debugging information > + lto Enable Link-Time Optimization. > sparse sparse checker > safe-stack SafeStack Stack Smash Protection. Depends on > clang/llvm >= 3.7 and requires coroutine backend ucontext. > @@ -7014,6 +7020,7 @@ NINJA=$ninja $meson setup \ > -Diconv=$iconv -Dcurses=$curses -Dlibudev=$libudev\ > -Ddocs=$docs -Dsphinx_build=$sphinx_build -Dinstall_blobs=$blobs \ > -Dvhost_user_blk_server=$vhost_user_blk_server \ > + -Db_lto=$lto \ > $cross_arg \ > "$PWD" "$source_path" > > diff --git a/meson.build b/meson.build > index e3386196ba..ebd1c690e0 100644 > --- a/meson.build > +++ b/meson.build > @@ -2044,6 +2044,7 @@ summary_info += {'gprof enabled': config_host.has_key('CONFIG_GPROF')} > summary_info += {'sparse enabled': sparse.found()} > summary_info += {'strip binaries': get_option('strip')} > summary_info += {'profiler': config_host.has_key('CONFIG_PROFILER')} > +summary_info += {'link-time optimization (LTO)': get_option('b_lto')} > summary_info += {'static build': config_host.has_key('CONFIG_STATIC')} > if targetos == 'darwin' > summary_info += {'Cocoa support': config_host.has_key('CONFIG_COCOA')} > I just came across this --enable-lto option ... but looking at the implementation here, it seems only to emit a line in the summary_info, without adding any compiler flags? Was this patch incomplete? Or do I miss something? Thomas
On 11/07/2021 12.22, Thomas Huth wrote: > On 05/12/2020 00.06, Daniele Buono wrote: >> This patch allows to compile QEMU with link-time optimization (LTO). >> Compilation with LTO is handled directly by meson. This patch only >> adds the option in configure and forwards the request to meson >> >> Tested with all major versions of clang from 6 to 12 >> >> Signed-off-by: Daniele Buono <dbuono@linux.vnet.ibm.com> >> --- >> configure | 7 +++++++ >> meson.build | 1 + >> 2 files changed, 8 insertions(+) >> >> diff --git a/configure b/configure >> index 18c26e0389..fee118518b 100755 >> --- a/configure >> +++ b/configure >> @@ -242,6 +242,7 @@ host_cc="cc" >> audio_win_int="" >> libs_qga="" >> debug_info="yes" >> +lto="false" >> stack_protector="" >> safe_stack="" >> use_containers="yes" >> @@ -1167,6 +1168,10 @@ for opt do >> ;; >> --disable-werror) werror="no" >> ;; >> + --enable-lto) lto="true" >> + ;; >> + --disable-lto) lto="false" >> + ;; >> --enable-stack-protector) stack_protector="yes" >> ;; >> --disable-stack-protector) stack_protector="no" >> @@ -1751,6 +1756,7 @@ disabled with --disable-FEATURE, default is enabled >> if available: >> module-upgrades try to load modules from alternate paths for upgrades >> debug-tcg TCG debugging (default is disabled) >> debug-info debugging information >> + lto Enable Link-Time Optimization. >> sparse sparse checker >> safe-stack SafeStack Stack Smash Protection. Depends on >> clang/llvm >= 3.7 and requires coroutine backend >> ucontext. >> @@ -7014,6 +7020,7 @@ NINJA=$ninja $meson setup \ >> -Diconv=$iconv -Dcurses=$curses -Dlibudev=$libudev\ >> -Ddocs=$docs -Dsphinx_build=$sphinx_build -Dinstall_blobs=$blobs \ >> -Dvhost_user_blk_server=$vhost_user_blk_server \ >> + -Db_lto=$lto \ >> $cross_arg \ >> "$PWD" "$source_path" >> diff --git a/meson.build b/meson.build >> index e3386196ba..ebd1c690e0 100644 >> --- a/meson.build >> +++ b/meson.build >> @@ -2044,6 +2044,7 @@ summary_info += {'gprof enabled': >> config_host.has_key('CONFIG_GPROF')} >> summary_info += {'sparse enabled': sparse.found()} >> summary_info += {'strip binaries': get_option('strip')} >> summary_info += {'profiler': >> config_host.has_key('CONFIG_PROFILER')} >> +summary_info += {'link-time optimization (LTO)': get_option('b_lto')} >> summary_info += {'static build': config_host.has_key('CONFIG_STATIC')} >> if targetos == 'darwin' >> summary_info += {'Cocoa support': config_host.has_key('CONFIG_COCOA')} >> > > I just came across this --enable-lto option ... but looking at the > implementation here, it seems only to emit a line in the summary_info, > without adding any compiler flags? Was this patch incomplete? Or do I miss > something? Never mind, I now learnt that b_lto is apparently an option that is directly understood by meson already :-) Thomas
diff --git a/configure b/configure index 18c26e0389..fee118518b 100755 --- a/configure +++ b/configure @@ -242,6 +242,7 @@ host_cc="cc" audio_win_int="" libs_qga="" debug_info="yes" +lto="false" stack_protector="" safe_stack="" use_containers="yes" @@ -1167,6 +1168,10 @@ for opt do ;; --disable-werror) werror="no" ;; + --enable-lto) lto="true" + ;; + --disable-lto) lto="false" + ;; --enable-stack-protector) stack_protector="yes" ;; --disable-stack-protector) stack_protector="no" @@ -1751,6 +1756,7 @@ disabled with --disable-FEATURE, default is enabled if available: module-upgrades try to load modules from alternate paths for upgrades debug-tcg TCG debugging (default is disabled) debug-info debugging information + lto Enable Link-Time Optimization. sparse sparse checker safe-stack SafeStack Stack Smash Protection. Depends on clang/llvm >= 3.7 and requires coroutine backend ucontext. @@ -7014,6 +7020,7 @@ NINJA=$ninja $meson setup \ -Diconv=$iconv -Dcurses=$curses -Dlibudev=$libudev\ -Ddocs=$docs -Dsphinx_build=$sphinx_build -Dinstall_blobs=$blobs \ -Dvhost_user_blk_server=$vhost_user_blk_server \ + -Db_lto=$lto \ $cross_arg \ "$PWD" "$source_path" diff --git a/meson.build b/meson.build index e3386196ba..ebd1c690e0 100644 --- a/meson.build +++ b/meson.build @@ -2044,6 +2044,7 @@ summary_info += {'gprof enabled': config_host.has_key('CONFIG_GPROF')} summary_info += {'sparse enabled': sparse.found()} summary_info += {'strip binaries': get_option('strip')} summary_info += {'profiler': config_host.has_key('CONFIG_PROFILER')} +summary_info += {'link-time optimization (LTO)': get_option('b_lto')} summary_info += {'static build': config_host.has_key('CONFIG_STATIC')} if targetos == 'darwin' summary_info += {'Cocoa support': config_host.has_key('CONFIG_COCOA')}
This patch allows to compile QEMU with link-time optimization (LTO). Compilation with LTO is handled directly by meson. This patch only adds the option in configure and forwards the request to meson Tested with all major versions of clang from 6 to 12 Signed-off-by: Daniele Buono <dbuono@linux.vnet.ibm.com> --- configure | 7 +++++++ meson.build | 1 + 2 files changed, 8 insertions(+)