Declare RTS-private prototypes with __attribute__((visibility("hidden")))

This has no effect with static libraries, but when the RTS is in a
shared library it does two things:

 - it prevents the function from being exposed by the shared library

 - internal calls to the function can use the faster non-PLT calls,
   because the function cannot be overriden at link time.

1 files changed, 8 insertions, 4 deletions

diff --git a/rts/sm/BlockAlloc.h b/rts/sm/BlockAlloc.h
index 776df9b627..86836e40b4 100644
--- a/rts/sm/BlockAlloc.h
+++ b/rts/sm/BlockAlloc.h
@@ -9,16 +9,20 @@
 #ifndef BLOCK_ALLOC_H
 #define BLOCK_ALLOC_H
 
+#pragma GCC visibility push(hidden)
+
 /* Debugging  -------------------------------------------------------------- */
 
 #ifdef DEBUG
-extern void checkFreeListSanity(void);
-nat         countFreeList(void);
-void        markBlocks (bdescr *bd);
-void        reportUnmarkedBlocks (void);
+void checkFreeListSanity(void);
+nat  countFreeList(void);
+void markBlocks (bdescr *bd);
+void reportUnmarkedBlocks (void);
 #endif
 
 extern lnat n_alloc_blocks;   // currently allocated blocks
 extern lnat hw_alloc_blocks;  // high-water allocated blocks
 
+#pragma GCC visibility pop
+
 #endif /* BLOCK_ALLOC_H */