Reduce <limits.h> pollution due to dynamic PTHREAD_STACK_MIN

<limits.h> used to be a header file with no declarations.
GCC's libgomp includes it in a #pragma GCC visibility hidden block.
Including <unistd.h> from <limits.h> (indirectly) declares everything
in <unistd.h> with hidden visibility, resulting in linker failures.

This commit avoids C declarations in assembler mode and only declares
__sysconf in <limits.h> (and not the entire contents of <unistd.h>).
The __sysconf symbol is already part of the ABI.  PTHREAD_STACK_MIN
is no longer defined for __USE_DYNAMIC_STACK_SIZE && __ASSEMBLER__
because there is no possible definition.

Additionally, PTHREAD_STACK_MIN is now defined by <pthread.h> for
__USE_MISC because this is what developers expect based on the macro
name.  It also helps to avoid libgomp linker failures in GCC because
libgomp includes <pthread.h> before its visibility hacks.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

1 files changed, 0 insertions, 7 deletions

diff --git a/include/bits/local_lim.h b/include/bits/local_lim.h
deleted file mode 100644
index 46d82dc729..0000000000
--- a/include/bits/local_lim.h
+++ /dev/null
@@ -1,7 +0,0 @@
-/* Don't define PTHREAD_STACK_MIN to sysconf (_SC_THREAD_STACK_MIN) for
-   glibc build.  */
-#if !defined _ISOMAC
-# undef __USE_DYNAMIC_STACK_SIZE
-#endif
-
-#include_next <bits/local_lim.h>