The use of the .hidden directive to avoid going via the PLT for
__set_errno had the side-effect of actually making __set_errno
hidden (which is odd because assembler directives don't usually
affect symbols defined in a different file --- you can't even
create a weak reference to a symbol that's defined in a different
file).
This change switches the system call stubs over to a new always-hidden
__set_errno_internal and has a visible __set_errno on LP32 just for
binary compatibility with old NDK apps.
(cherry-pick of 7efad83d430f4d824f2aaa75edea5106f6ff8aae.)
Bug: 17423135
Change-Id: I6b6d7a05dda85f923d22e5ffd169a91e23499b7b
__set_errno returns -1 exactly so that callers don't need to bother.
The other architectures were already taking advantage of this, but
no one had ever fixed x86 and x86_64.
Change-Id: Ie131494be664f6c4a1bbf8c61bbbed58eac56122
We only need it for MAX_ERRNO, and it's time we had somewhere to put
the little assembler utility macros we've been putting off writing.
Change-Id: I9354d2e0dc47c689296a34b5b229fc9ba75f1a83
