Fix native powerpc64 build of lib32 with in-tree GCC.

- This was broken by r300350 and r300885.
- Add some comments around the external GCC logic since it is spread out
  and in need of some cleanup.
- The problem was that X_COMPILER_TYPE is always defined from CC->XCC's
  default, so if /usr/bin/cc is GCC (as it is on native powerpc64) then
  X_COMPILER_TYPE was getting GCC and triggering the external logic in
  Makefile.libcompat.  It was intended to always provide -isystem with
  GCC since --sysroot is used into the lib32 sysroot which won't modify
  the header path without the -isystem.  The use of the libc++/std=c++11
  override was only intended to be used for external compilers though
  (more accurately GCC 4.8+ but that's a separate assumption to
  cleanup).  Apply the same logic from Makefile.inc1 to Makefile.libcompat
  to only add the libc++ override when needed for external compilers.

Pointyhat to:	bdrewery
Tested with:	native ppc64 (swills), universe, ppc64 xtoolchain,
		amd64 xtoolchain, sparc64 cross-build of ppc64 (host GCC 4.2)
Reported by:	andreast, swills
Approved by:	re (gjb)
Sponsored by:	EMC / Isilon Storage Division

1 files changed, 4 insertions, 1 deletions

diff --git a/Makefile.inc1 b/Makefile.inc1
index 0daa440..ab028a6 100644
--- a/Makefile.inc1
+++ b/Makefile.inc1
@@ -543,9 +543,12 @@ TARGET_ABI=	gnueabi
 .endif
 .endif
 .if defined(X_COMPILER_TYPE) && ${X_COMPILER_TYPE} == gcc
-# GCC requires -isystem and -L when using a cross-compiler.
+# GCC requires -isystem and -L when using a cross-compiler.  --sysroot
+# won't set header path and -L is used to ensure the base library path
+# is added before the port PREFIX library path.
 XCFLAGS+=	-isystem ${WORLDTMP}/usr/include -L${WORLDTMP}/usr/lib
 # Force using libc++ for external GCC.
+# XXX: This should be checking MK_GNUCXX == no
 XCXXFLAGS+=	-isystem ${WORLDTMP}/usr/include/c++/v1 -std=c++11 \
 		-nostdinc++ -L${WORLDTMP}/../lib/libc++
 .else