[PATCH] D15883: Add ARM EHABI-related constants to unwind.h.

[Saleem Abdulrasool via cfe-commits]

compnerd added a comment.

This change seems fine to me as is, just waiting to iron out the macro situation with @logan before accepting it.


================
Comment at: lib/Headers/unwind.h:61
@@ +60,3 @@
+#define _UNWIND_ARM_EHABI 0
+#endif
+
----------------
logan wrote:
> Since this is `unwind.h`, I feel that we can get a step further and use `__ARM_EABI_UNWINDER__` to get more compatibility to GCC's unwind.h.
> 
> Here's the change:
> 
> ```
> #if defined(__arm__) && !defined(__USING_SJLJ_EXCEPTIONS__) && \
>     !defined(__ARM_DWARF_EH__)
> #define __ARM_EABI_UNWINDER__ 1
> #endif
> ```
I dont know if we really need to imitate GCC's macros here.  Am I mistaken in that they assume that `__ARM_EABI_UNWINDER__` has been set to 1 externally if targeting such an environment?  I think that it is better to use the reserved namespace and intrude into libunwind's namespace as already done here.


http://reviews.llvm.org/D15883