[llgo] Roll gofrontend forward

Switch gofrontend to using go.googlesource.com, and
update to 81eb6a3f425b2158c67ee32c0cc973a72ce9d6be.

There are various changes required to update to the
go 1.5 runtime:

typemap.go is changed to accommodate the change in representation for equal/hash algorithms, and the removal of the zero value/type.
CMakeLists.txt is updated to add the build tree to the package search path, so internal packages, which are not installed, are found.
various files changes due to removal of __go_new_nopointers; the same change as in D11863, but with NoUnwindAttribute added to the added runtime functions which are called with "callOnly".
minor cleanups in ssa.go while investigating issues with unwinding/panic handling.

Differential Revisision: http://reviews.llvm.org/D15188

llvm-svn: 263536

1 files changed, 8 insertions, 3 deletions

diff --git a/llgo/third_party/gofrontend/libgo/runtime/env_posix.c b/llgo/third_party/gofrontend/libgo/runtime/env_posix.c
index ee3e4514554..b93edd65a6b 100644
--- a/llgo/third_party/gofrontend/libgo/runtime/env_posix.c
+++ b/llgo/third_party/gofrontend/libgo/runtime/env_posix.c
@@ -11,7 +11,7 @@
 
 extern Slice envs;
 
-const byte*
+String
 runtime_getenv(const char *s)
 {
 	int32 i, j;
@@ -19,6 +19,7 @@ runtime_getenv(const char *s)
 	const byte *v, *bs;
 	String* envv;
 	int32 envc;
+	String ret;
 
 	bs = (const byte*)s;
 	len = runtime_findnull(bs);
@@ -33,8 +34,12 @@ runtime_getenv(const char *s)
 				goto nomatch;
 		if(v[len] != '=')
 			goto nomatch;
-		return v+len+1;
+		ret.str = v+len+1;
+		ret.len = envv[i].len-len-1;
+		return ret;
 	nomatch:;
 	}
-	return nil;
+	ret.str = nil;
+	ret.len = 0;
+	return ret;
 }