Extend configure's __int128 test to check for a known gcc bug.
On Sparc64, use of __attribute__(aligned(8)) with __int128 causes faulty
code generation in gcc versions at least through 5.5.0. We can work around
that by disabling use of __int128, so teach configure to test for the bug.
This solution doesn't fix things for the case of cross-compiling with a
buggy compiler; to support that nicely, we'd need to add a manual disable
switch. Unless more such cases turn up, it doesn't seem worth the work.
Affected users could always edit pg_config.h manually.
In passing, fix some typos in the existing configure test for __int128.
They're harmless because we only compile that code not run it, but
they're still confusing for anyone looking at it closely.
This is needed in support of commit 751804998, so back-patch to 9.5
as that was.
Marina Polyakova, Victor Wagner, Tom Lane
Discussion: https://postgr.es/m/0d3a9fa264cebe1cb9966f37b7c06e86@postgrespro.ru
Branch
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REL9_6_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/456cab29df65b7ad3d9ce6345bb85448d7c8f98e
Modified Files
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config/c-compiler.m4 | 48 +++++++++++++++++++++++++++++------
configure | 72 +++++++++++++++++++++++++++++++++++++++++++++++-----
2 files changed, 105 insertions(+), 15 deletions(-)