Fix build issues with clang 3.4

clang 3.4 (just like gcc) implements _Unwind_GetIP - use Bionic's
implementation only if older clang versions are used.

Don't set incorrect values for WCHAR_MIN and WCHAR_MAX when using clang
in c++11 mode (c++11 has a builtin wchar_t that happens to be unsigned
in clang). Signed WCHAR_MIN and WCHAR_MAX defines in clang++ -std=c++11
cause anything using stlport to fail.

Change-Id: I46ed08b873f34e01c5e66aa8d91c71478bfcc25d
Signed-off-by: Bernhard Rosenkränzer <Bernhard.Rosenkranzer@linaro.org>

Conflicts:
	libc/bionic/debug_stacktrace.cpp
	libc/include/stdint.h
<sys/cdefs.h>: Fix clang __used__ attribute handling

Clang ignores and does not currently support the __used__ attribute

Change-Id: I1a7838136fed4f2dcdb7e04347312d98e5d0fd65
Fix inconsistent 'extern inline' default behavior between GCC and Clang.

Otherwise, we may get 'symbol multiple definition' error on some conditions
when linking two modules including <ctype.h> compiled by Clang.

http://clang.llvm.org/compatibility.html#inline

Change-Id: I969e58607eea818aef95270ec725f47dfb244e88

Conflicts:
	libc/include/ctype.h
Extra tests for printf of NaN and Inf.

Change-Id: I61fc655d9777a03aabf38f6ebd047fe275386f05

Conflicts:
	tests/stdio_test.cpp
Switch fpclassify over to ieee_ext.

Change-Id: I441bb7f715da24e1c04b0386ad9dcde0ea8c797c

Conflicts:
	libc/bionic/fpclassify.cpp
Clean up <machine/ieee.h>.

The upstream intention was for this to be architecture-dependent, but it's a
lot clearer if we just have one copy.

Change-Id: I4e8310496145f9f411cd2e847c8cd023b1d758e9

Conflicts:
	libc/arch-arm/include/machine/ieee.h
	libc/arch-x86/include/machine/ieee.h
	libc/include/machine/ieee.h
Revert "Remove non-standard memswap."

This reverts commit 616b47a8db13645a671c6118450ec7817fe72c22.