sys-devel/gcc: Fails to compile with jit USE

[TheGreatMcPain]

When emerging sys-devel/gcc with the jit useflag it fails to configure build-jit/gcc with this error.

checking size of int... 0
checking size of long... 0
checking for long long... yes
checking size of long long... configure: error: in `/var/tmp/portage/sys-devel/gcc-11.3.0/work/build-jit/gcc':
configure: error: cannot compute sizeof (long long)
See `config.log' for more details
make[1]: *** [Makefile:4366: configure-gcc] Error 1
make[1]: Leaving directory '/var/tmp/portage/sys-devel/gcc-11.3.0/work/build-jit'
make: *** [Makefile:956: all] Error 2

Looking at work/build-jit/gcc/config.log I noticed it put -Wl,-Wl,--as-needed causing ld to fail.

configure:6293: result: 0
configure:6307: checking size of long
configure:6312: x86_64-pc-linux-gnu-g++ -o conftest -march=native -pipe -Wl,-Wl,--as-needed -O2   -static-libstdc++ -static-libgcc -Wl,-O1 -Wl,--as-needed -march=native -pipe conftest.cpp  >&5
/usr/lib/gcc/x86_64-pc-linux-gnu/11.2.1/../../../../x86_64-pc-linux-gnu/bin/ld: unrecognized option '-Wl'
/usr/lib/gcc/x86_64-pc-linux-gnu/11.2.1/../../../../x86_64-pc-linux-gnu/bin/ld: use the --help option for usage information
collect2: error: ld returned 1 exit status
configure:6312: $? = 1
configure: program exited with status 1

Adding sys-devel/gcc NOLDADD=1 to package.cflags seems to work.

I think this started happening after this commit to toolchain.eclass.

EDIT: Here's some log files if they're needed.
emerge --info
emerge --info sys-devel/gcc
/var/tmp/portage/sys-devel/gcc-11.3.0/temp/build.log.
/var/tmp/portage/sys-devel/gcc-11.3.0/work/build-jit/gcc/config.log

[BorisCarvajal]

Confirmed, this code path wasn't taken before the change in toolchain.eclass and it's messing up our linker argument.
I should probably report it to gcc bugzilla.

Here is a temporary fix.

/etc/portage/patches/sys-devel/gcc/fix_sed.patch:

--- a/gcc/configure	2022-06-02 03:40:20.557616640 -0400
+++ b/gcc/configure	2022-06-02 03:41:33.216325056 -0400
@@ -5392,8 +5392,8 @@
 # optimizations to be activated explicitly by the toplevel.
 case "$CC" in
   */prev-gcc/xgcc*) ;;
-  *) CFLAGS=`echo "$CFLAGS " | sed -e "s/-Ofast[ 	]//" -e "s/-O[gs][ 	]//" -e "s/-O[0-9]*[ 	]//" `
-     CXXFLAGS=`echo "$CXXFLAGS " | sed -e "s/-Ofast[ 	]//" -e "s/-O[gs][ 	]//" -e "s/-O[0-9]*[ 	]//" ` ;;
+  *) CFLAGS=`echo "$CFLAGS " | sed -e "s/-Ofast[ 	]//" -e "s/-O[gs][ 	]//" -e "s/\(^\|[ 	]\)-O[0-9]*[ 	]/\1/" `
+     CXXFLAGS=`echo "$CXXFLAGS " | sed -e "s/-Ofast[ 	]//" -e "s/-O[gs][ 	]//" -e "s/\(^\|[ 	]\)-O[0-9]*[ 	]/\1/" ` ;;
 esac
 
 

[thesamesam]

See discussion on Gentoo's Bugzilla. @ionenwks noticed that it's because the JIT path has --disable-bootstrap so we just happened to never hit it before.

As per my comment on Bugzilla, while this is a bug, it's niche, and you can easily avoid it by not stuffing LDFLAGS into CFLAGS unnecessarily.

[thesamesam]

There's a fix in ::gentoo for 10.4+/11.3+/12 now, so this can be closed. But as per my comment on Bugzilla, I'd still really suggest disabling the flag mangling from bashrc anyway.