x86_64-pc-linux-gnu-g++ -o nsBMPDecoder.o -c -I../../../dist/stl_wrappers -I../../../dist/system_wrappers -include /var/tmp/portage/www-client/firefox-7.0.1/work/mozilla-release/config/gcc_hidden.h -DMOZ_PNG_WRITE -DMOZ_PNG_READ -DMOZILLA_INTERNAL_API -D_IMPL_NS_COM -DEXPORT_XPT_API -DEXPORT_XPTC_API -D_IMPL_NS_GFX -D_IMPL_NS_WIDGET -DIMPL_XREAPI -DIMPL_NS_NET -DIMPL_THEBES -DSTATIC_EXPORTABLE_JS_API -DOSTYPE=\"Linux2.6\" -DOSARCH=Linux -I/var/tmp/portage/www-client/firefox-7.0.1/work/mozilla-release/modules/libpr0n/src/ -I/var/tmp/portage/www-client/firefox-7.0.1/work/mozilla-release/modules/libpr0n/decoders -I. -I../../../dist/include -I../../../dist/include/nsprpub -I/usr/include/nspr -I/usr/include/nss -fPIC -fno-rtti -fno-exceptions -Wall -Wpointer-arith -Woverloaded-virtual -Wsynth -Wno-ctor-dtor-privacy -Wno-non-virtual-dtor -Wcast-align -Wno-invalid-offsetof -Wno-variadic-macros -Werror=return-type -march=native -mno-avx -ffunction-sections -fdata-sections -fno-strict-aliasing -std=gnu++0x -pthread -pipe -DNDEBUG -DTRIMMED -g -fprofile-generate -O1 -DMOZILLA_CLIENT -include ../../../mozilla-config.h -MD -MF .deps/nsBMPDecoder.pp /var/tmp/portage/www-client/firefox-7.0.1/work/mozilla-release/modules/libpr0n/decoders/nsBMPDecoder.cpp amd64box ~ # emerge --info | grep CXX CXXFLAGS="-march=native -O2" -O1 passed instead of -O2 and there is also -g
There are known parts of the build system that are overridden, we will not patch them out, the build system is fragile enough without introducing crazy cflags.