From 07730ff3465d3cede3026cdd1c17453930f055ce Mon Sep 17 00:00:00 2001 From: Andre Heider Date: Thu, 2 Feb 2023 21:33:38 +0100 Subject: treewide: add support for "lto" in PKG_BUILD_FLAGS This reduces open coding and allows to easily add a knob to enable it treewide, where chosen packages can still opt-out via "no-lto". Some packages used LTO, but not the linker plugin. This unifies 'em all to attempt to produce better code. Quoting man gcc(1): "This improves the quality of optimization by exposing more code to the link-time optimizer." Also use -flto=auto instead of -flto=jobserver, as it's not guaranteed that every buildsystem uses +$(MAKE) correctly. Signed-off-by: Andre Heider --- include/package.mk | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'include/package.mk') diff --git a/include/package.mk b/include/package.mk index 4d97cda00f..0fb947f035 100644 --- a/include/package.mk +++ b/include/package.mk @@ -30,7 +30,7 @@ ifneq ($(strip $(PKG_USE_MIPS16)),1) PKG_BUILD_FLAGS+=no-mips16 endif -__unknown_flags=$(filter-out no-iremap no-mips16 gc-sections no-gc-sections,$(PKG_BUILD_FLAGS)) +__unknown_flags=$(filter-out no-iremap no-mips16 gc-sections no-gc-sections lto no-lto,$(PKG_BUILD_FLAGS)) ifneq ($(__unknown_flags),) $(error unknown PKG_BUILD_FLAGS: $(__unknown_flags)) endif @@ -56,6 +56,11 @@ ifeq ($(call pkg_build_flag,gc-sections,0),1) TARGET_CXXFLAGS+= -ffunction-sections -fdata-sections TARGET_LDFLAGS+= -Wl,--gc-sections endif +ifeq ($(call pkg_build_flag,lto,0),1) + TARGET_CFLAGS+= -flto=auto -fno-fat-lto-objects + TARGET_CXXFLAGS+= -flto=auto -fno-fat-lto-objects + TARGET_LDFLAGS+= -flto=auto -fuse-linker-plugin +endif include $(INCLUDE_DIR)/hardening.mk include $(INCLUDE_DIR)/prereq.mk -- cgit v1.2.3