cc-wrapper/add-hardening.sh: always unset _FORTIFY_SOURCE before re-setting it

On darwin clang driver always sets -D_FORTIFY_SOURCE=0 under asan.
This causes -Werror to trip over macro redefinition:

    <command line>:1:9: error: '_FORTIFY_SOURCE' macro redefined [-Werror,-Wmacro-redefined]
    #define _FORTIFY_SOURCE 2
            ^

To avoid it let's always explicitly undefine it first before redefining.
This commit is contained in:
Sergei Trofimovich 2022-10-01 08:27:38 +01:00
parent f32a43f6de
commit 2a9fc04635

View file

@ -38,7 +38,9 @@ for flag in "${!hardeningEnableMap[@]}"; do
case $flag in
fortify)
if (( "${NIX_DEBUG:-0}" >= 1 )); then echo HARDENING: enabling fortify >&2; fi
hardeningCFlags+=('-O2' '-D_FORTIFY_SOURCE=2')
# Use -U_FORTIFY_SOURCE to avoid warnings on toolchains that explicitly
# set -D_FORTIFY_SOURCE=0 (like 'clang -fsanitize=address').
hardeningCFlags+=('-O2' '-U_FORTIFY_SOURCE' '-D_FORTIFY_SOURCE=2')
;;
stackprotector)
if (( "${NIX_DEBUG:-0}" >= 1 )); then echo HARDENING: enabling stackprotector >&2; fi