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')}