configure: Don't assume an aligned stack on clang on windows
authorMartin Storsjö <martin@martin.st>
Mon, 12 Mar 2018 22:13:55 +0000 (00:13 +0200)
committerMartin Storsjö <martin@martin.st>
Tue, 13 Mar 2018 13:25:12 +0000 (15:25 +0200)
commit847190ebd99ffd57dc89bd568a33bf2d5c424129
tree5d91c54b541db9f9946a5b30b7956089bb722d2c
parent43778a501f1bfbceeddc8eaeea2ea2b3506beeda
configure: Don't assume an aligned stack on clang on windows

If we'd enable a 16 byte aligned stack, clang/llvm would also assume
that alignment everywhere and produce code that strictly requires it.
That would require adding realignment (via attribute_align_arg) on every
single public library function or enable -mstackrealign (which does the
same on every single function).

Also relatedly; the parameter currently tested (-mllvm
-stack-alignment=16) hasn't actually been supported for quite some
time; current clang versions use -mstack-alignment=16 for the same.
Actually testing for that parameter would be a different change
though, since it has a real risk of changing behaviour on any other
platform where clang is used.

Signed-off-by: Martin Storsjö <martin@martin.st>
configure