From ee228403e9741b6c799ce1ef34c15993086f266d Mon Sep 17 00:00:00 2001 From: Norbert Lange Date: Sun, 18 Oct 2020 00:17:41 +0200 Subject: [PATCH] package/gcc: use binutils wrappers for target libs This will use gcc-ar, gcc-nm and gcc-ranlib instead of the normal binutils tools. The difference is that with the wrappers, gcc plugins will be automatically picked up, which is necessary to build with LTO. With this enabled, it is possible to build everything (including libgcc and libstdc++) with LTO by setting BR2_TARGET_OPTIMIZATION="-flto". Note that you'd expect that the GCC build system would automatically do this when --enable-lto is set, but this is not the case. There are some open bugs [1][2] to allow building libgcc and libstdc++ with LTO support but it's apparently not done yet. Note that there are also reports of problems building libstdc++ with LTO [3], but it seems that's no longer a problem (and the bug didn't get updated). Signed-off-by: Norbert Lange Signed-off-by: Arnout Vandecappelle (Essensium/Mind) [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59893 [2] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77278 [3] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60160 --- package/gcc/gcc.mk | 1 + 1 file changed, 1 insertion(+) diff --git a/package/gcc/gcc.mk b/package/gcc/gcc.mk index 3adc1d4e16..128cf8421d 100644 --- a/package/gcc/gcc.mk +++ b/package/gcc/gcc.mk @@ -104,6 +104,7 @@ endif # Propagate options used for target software building to GCC target libs HOST_GCC_COMMON_CONF_ENV += CFLAGS_FOR_TARGET="$(GCC_COMMON_TARGET_CFLAGS)" HOST_GCC_COMMON_CONF_ENV += CXXFLAGS_FOR_TARGET="$(GCC_COMMON_TARGET_CXXFLAGS)" +HOST_GCC_COMMON_CONF_ENV += AR_FOR_TARGET=gcc-ar NM_FOR_TARGET=gcc-nm RANLIB_FOR_TARGET=gcc-ranlib # libitm needs sparc V9+ ifeq ($(BR2_sparc_v8)$(BR2_sparc_leon3),y)