Sergei Trofimovich 34636efced gcc: pass --with-build-sysroot=/ for gcc builds ... Without this change cross-built gcc fails to detect stack protector style: $ nix log -f pkgs/stdenv/linux/make-bootstrap-tools-cross.nix powerpc64le.bootGCC | fgrep __stack_chk_fail checking __stack_chk_fail in target C library... no checking __stack_chk_fail in target C library... no It happens because gcc treats search paths differently: https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=gcc/configure.ac;h=446747311a6aec3c810ad6aa4190f7bd383b94f7;hb=HEAD#l2458 if test x$host != x$target || test "x$TARGET_SYSTEM_ROOT" != x || test x$build != x$host || test "x$with_build_sysroot" != x; then ... if test "x$with_build_sysroot" != "x"; then target_header_dir="${with_build_sysroot}${native_system_header_dir}" elif test "x$with_sysroot" = x; then target_header_dir="${test_exec_prefix}/${target_noncanonical}/sys-include" elif test "x$with_sysroot" = xyes; then target_header_dir="${test_exec_prefix}/${target_noncanonical}/sys-root${native_system_header_dir}" else target_header_dir="${with_sysroot}${native_system_header_dir}" fi else target_header_dir=${native_system_header_dir} fi By passing --with-build-sysroot=/ we trick cross-case to use `target_header_dir="${with_sysroot}${native_system_header_dir}"` which makes it equivalent to non-cross `target_header_dir="${with_build_sysroot}${native_system_header_dir}"` Tested the following setups: - cross-compiler without libc headers (powerpc64le-static) - cross-compiler with libc headers (powerpc64le-debug) - cross-build compiler with libc headers (powerpc64le bootstrapTools) Before the change only 2 of 3 compilers detected libc headers. After the change all 3 compilers detected libc headers. For darwin we silently ignore '-syslibroot //' argument as it does not introduce impurities. While at it dropped mingw special case for no-libc build. Before the change we passed both '--without-headers --with-native-system-headers-dir' for no-libc gcc-static builds. This tricked darwin builds to find sys/sdt.h and fail inhibid_libc builds. Now all targets avoid passing native headers for gcc-static builds. While at it fixed correct headers passing to --with-native-system-headers-dir= in host != target case: we were passing host's headers where intention was to pass target's headers. Noticed the mismatch as a build failure on pkgsCross.powernv.stdenv.cc on darwin where `sys/sdt.h` is present in host's headers (libSystem) but not target's headers (`glibc`). Co-authored-by: Adam Joseph <54836058+amjoseph-nixpkgs@users.noreply.github.com>		2022-07-23 18:40:07 +01:00
..
configure-flags.nix	gcc: pass --with-build-sysroot=/ for gcc builds	2022-07-23 18:40:07 +01:00
extra-target-flags.nix
platform-flags.nix
pre-configure.nix