configure: Always use AC_LINK_ELSEIF when testing against assembler wip/ghc-8.6.5
authorBen Gamari <ben@smart-cactus.org>
Sun, 31 Mar 2019 20:00:34 +0000 (16:00 -0400)
committerBen Gamari <ben@smart-cactus.org>
Wed, 3 Apr 2019 11:45:56 +0000 (07:45 -0400)
commit31732efcb4de06ae0714989998eb29238cb48a1e
tree3cace6f46807371344d8ef975973767e1cd8efda
parent42eb3a5e2409b7ca07d8f18ceef0d7d515c5fbec
configure: Always use AC_LINK_ELSEIF when testing against assembler

This fixes #16440, where the build system incorrectly concluded that the
`.subsections_via_symbols` assembler directive was supported on a Linux
system. This was caused by the fact that gcc was invoked with `-flto`;
when so-configured gcc does not call the assembler but rather simply
serialises its AST for compilation during the final link.

This is described in Note [autoconf assembler checks and -flto].

(cherry picked from commit 7b090b53fea065d2cfd967ea919426af9ba8d737)
aclocal.m4