openssl build with -Werror and thus fails with deprecated CFLAGS. See log below: * abi_x86_32.x86: running multilib-minimal_abi_src_compile make -j9 -j1 V=1 depend making depend in crypto... make[1]: Entering directory '/var/tmp/portage/dev-libs/openssl-1.0.2p/work/openssl-1.0.2p-abi_x86_32.x86/crypto' cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors cc1: error: '-mtune=x86-64' is deprecated; use '-mtune=k8' or '-mtune=generic' instead as appropriate [-Werror=deprecated] cc1: all warnings being treated as errors make[1]: *** [Makefile:137: local_depend] Error 1 make[1]: Leaving directory '/var/tmp/portage/dev-libs/openssl-1.0.2p/work/openssl-1.0.2p-abi_x86_32.x86/crypto' make: *** [Makefile:487: depend] Error 1
It looks like -Werror is really only used when calculating dependencies (the "depend" target). I think it comes from util/domd.