toolchain-glibc.eclass: fix glibc-headers bootstrap on non-multilib host

The error is found by wm_ attempting to build a cross-compiler
    CHOST=powerpc-unknown-linux-gnu CTARGET=mips64-unknown-linux-gnu
Boostrap failed on glibc-headers (./configure phase) as:

  configure:2623: powerpc-unknown-linux-gnu-gcc -mabi=n32 -c -O1 -pipe -U_FORTIFY_SOURCE conftest.c >&5
  powerpc-unknown-linux-gnu-gcc: error: unrecognized command line option '-mabi=n32'; did you mean '-mabi=d32'?

Note how target's ABI is mexed into host's compiler flags.

The error above happens on every host=non-multilib target=multilib combination.
I've reproduced it on:
    CHOST=i686-pc-linux-gnu CTARGET=mips64-unknown-linux-gnu

The fix is not to inject target's CFLAGS ABI into CC for
USE=headers-only bootstrap step as we don't have cross-compiler yet.

Tested by successfully bootstrapping cross-compiler on
    CHOST=i686-pc-linux-gnu CTARGET=mips64-unknown-linux-gnu

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>

diff --git a/eclass/toolchain-glibc.eclass b/eclass/toolchain-glibc.eclass
index bd10f2cbbe40e189a79fa98ac10d9200235b9611..d75ca2eefdf59b1dc0c33bdca90da56d17438cb0 100644 (file)
--- a/eclass/toolchain-glibc.eclass
+++ b/eclass/toolchain-glibc.eclass
@@ -370,6 +370,14 @@ setup_env() {
 
        export ABI=${ABI:-${DEFAULT_ABI:-default}}
 
+       if use headers-only ; then
+               # Avoid mixing host's CC and target's CFLAGS_${ABI}:
+               # At this bootstrap stage we have only binutils for
+               # target but not compiler yet.
+               einfo "Skip CC ABI injection. We can't use (cross-)compiler yet."
+               return 0
+       fi
+
        local VAR=CFLAGS_${ABI}
        # We need to export CFLAGS with abi information in them because glibc's
        # configure script checks CFLAGS for some targets (like mips).  Keep