Hmm, emerge --info from before and after (with added -fstack-check) looks dodgy
# tail bind.info ================================================================= Package Settings ================================================================= net-dns/bind-9.11.1_p1::gentoo was built with the following: USE="berkdb caps dlz filter-aaaa ipv6 ssl threads xml zlib -dnstap -doc -fixed-rrset -geoip -gost -gssapi -idn -json -ldap -libressl -lmdb -mysql -nslint -odbc -postgres -python -rpz (-seccomp) (-selinux) -static-libs -urandom" ABI_X86="(64)" PYTHON_TARGETS="python2_7 python3_4 -python3_5 -python3_6" CFLAGS="-O2 -march=amdfam10 -mcx16 -mpopcnt -pipe -msahf -mabm -fomit-frame-pointer -I/usr/include/db5.3" CXXFLAGS="-O2 -march=amdfam10 -mcx16 -mpopcnt -pipe -msahf -mabm -fomit-frame-pointer -I/usr/include/db5.3" LDFLAGS="-Wl,-O1 -Wl,--as-needed -O2 -march=amdfam10 -mcx16 -mpopcnt -pipe -msahf -mabm -fomit-frame-pointer" # tail bind.info2 ================================================================= Package Settings ================================================================= net-dns/bind-9.11.1_p1::gentoo was built with the following: USE="berkdb caps dlz filter-aaaa ipv6 ssl threads xml zlib -dnstap -doc -fixed-rrset -geoip -gost -gssapi -idn -json -ldap -libressl -lmdb -mysql -nslint -odbc -postgres -python -rpz (-seccomp) (-selinux) -static-libs -urandom" ABI_X86="(64)" PYTHON_TARGETS="python2_7 python3_4 -python3_5 -python3_6" CFLAGS="-O2 -march=amdfam10 -mcx16 -mpopcnt -pipe -msahf -mabm -fomit-frame-pointer -fstack-check -I/usr/include/db5.3" CXXFLAGS="-O2 -march=amdfam10 -mcx16 -mpopcnt -pipe -msahf -mabm -fomit-frame-pointer -fstack-check -I/usr/include/db5.3" ===> LDFLAGS has been clobbered # tail apache.info ================================================================= Package Settings ================================================================= www-servers/apache-2.4.25::gentoo was built with the following: USE="ssl threads -debug -doc -ldap (-libressl) (-selinux) -static -suexec" ABI_X86="(64)" APACHE2_MODULES="actions alias auth_basic auth_digest authn_alias authn_anon authn_core authn_dbm authn_file authz_core authz_dbm authz_groupfile authz_host authz_owner authz_user autoindex cache cgi cgid dav dav_fs dav_lock deflate dir env expires ext_filter file_cache filter headers http2 include info log_config logio mime mime_magic negotiation proxy proxy_connect proxy_http rewrite setenvif socache_shmcb speling status unique_id unixd userdir usertrack vhost_alias -access_compat -asis -authn_dbd -authz_dbd -cache_disk -cache_socache -cern_meta -charset_lite -dbd -dumpio -ident -imagemap -lbmethod_bybusyness -lbmethod_byrequests -lbmethod_bytraffic -lbmethod_heartbeat -log_forensic -macro -proxy_ajp -proxy_balancer -proxy_fcgi -proxy_ftp -proxy_html -proxy_scgi -proxy_wstunnel -ratelimit -remoteip -reqtimeout -slotmem_shm -substitute -version" APACHE2_MPMS="-event -prefork -worker" CFLAGS="-O2 -march=amdfam10 -mcx16 -mpopcnt -pipe -msahf -mabm -fomit-frame-pointer -fPIC" CXXFLAGS="-O2 -march=amdfam10 -mcx16 -mpopcnt -pipe -msahf -mabm -fomit-frame-pointer -fPIC" LDFLAGS="-Wl,-O1 -Wl,--as-needed -O2 -march=amdfam10 -mcx16 -mpopcnt -pipe -msahf -mabm -fomit-frame-pointer -fPIC -Wl,--no-as-needed" # tail apache.info2 Unset: CC, CPPFLAGS, CTARGET, CXX, INSTALL_MASK, LC_ALL, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS, USE_PYTHON ================================================================= Package Settings ================================================================= www-servers/apache-2.4.25::gentoo was built with the following: USE="ssl threads -debug -doc -ldap (-libressl) (-selinux) -static -suexec" ABI_X86="(64)" APACHE2_MODULES="actions alias auth_basic auth_digest authn_alias authn_anon authn_core authn_dbm authn_file authz_core authz_dbm authz_groupfile authz_host authz_owner authz_user autoindex cache cgi cgid dav dav_fs dav_lock deflate dir env expires ext_filter file_cache filter headers http2 include info log_config logio mime mime_magic negotiation proxy proxy_connect proxy_http rewrite setenvif socache_shmcb speling status unique_id unixd userdir usertrack vhost_alias -access_compat -asis -authn_dbd -authz_dbd -cache_disk -cache_socache -cern_meta -charset_lite -dbd -dumpio -ident -imagemap -lbmethod_bybusyness -lbmethod_byrequests -lbmethod_bytraffic -lbmethod_heartbeat -log_forensic -macro -proxy_ajp -proxy_balancer -proxy_fcgi -proxy_ftp -proxy_html -proxy_scgi -proxy_wstunnel -ratelimit -remoteip -reqtimeout -slotmem_shm -substitute -version" APACHE2_MPMS="-event -prefork -worker" LDFLAGS="-Wl,-O1 -Wl,--as-needed -O2 -march=amdfam10 -mcx16 -mpopcnt -pipe -msahf -mabm -fomit-frame-pointer -fstack-check -Wl,--no-as-needed" ====> CFLAGS and CXXFLAGS clobbered I assume this behaviour in unintentional....