This is currently only supported when CC_FOR_BUILD is available, as that
ultimately governs what the native ABI is. Ideally we would always have
a compiler present, and there's very little use for config.guess without
one, but this at least avoids breaking existing setups. A fallback using
objdump -f `command -v uname` | grep -q elf32-x86-64
could be used even in the absence of a compiler, though a perfectly
valid environment could still have that as an amd64 binary, if unlikely.
We shouldn't check /bin/sh, however, as klibc builds that as an amd64
binary even for x32 (see [0]).
[0] https://lists.gnu.org/archive/html/config-patches/2018-03/msg00002.html
---
config.guess | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/config.guess b/config.guess
index 11fda52..92bfc33 100755
--- a/config.guess
+++ b/config.guess
@@ -1095,7 +1095,17 @@ EOF
echo "$UNAME_MACHINE"-dec-linux-"$LIBC"
exit ;;
x86_64:Linux:*:*)
- echo "$UNAME_MACHINE"-pc-linux-"$LIBC"
+ set_cc_for_build
+ LIBCABI=$LIBC
+ if [ "$CC_FOR_BUILD" != no_compiler_found ]; then
+ if (echo '#ifdef __ILP32__'; echo IS_X32; echo '#endif') | \
+ (CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
+ grep IS_X32 >/dev/null
+ then
+ LIBCABI="$LIBC"x32
+ fi
+ fi
+ echo "$UNAME_MACHINE"-pc-linux-"$LIBCABI"
exit ;;
xtensa*:Linux:*:*)
echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
--
2.20.1
