libgo patch committed: Recognize PPC PC in signal handler

[Ian Lance Taylor]

This patch to libgo changes the signal handler for PPC (and PPC64)
GNU/Linux to fetch the PC from the signal context.  Bootstrapped and
ran Go testsuite on x86_64-pc-linux-gnu and
powerpc64le-unknown-linux-gnu.  Committed to mainline.

Ian

Index: gcc/go/gofrontend/MERGE
===================================================================
--- gcc/go/gofrontend/MERGE     (revision 250433)
+++ gcc/go/gofrontend/MERGE     (working copy)
@@ -1,4 +1,4 @@
-e34cb8dee6c1f215329e0eea79202b48cb83817c
+a9f1aeced86691de891fbf2a8c97e848faf1962e
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.
Index: libgo/runtime/go-signal.c
===================================================================
--- libgo/runtime/go-signal.c   (revision 250406)
+++ libgo/runtime/go-signal.c   (working copy)
@@ -215,6 +215,11 @@ getSiginfo(siginfo_t *info, void *contex
        ret.sigpc = ((ucontext_t*)(context))->uc_mcontext.gregs[REG_EIP];
   #endif
 #endif
+#ifdef __PPC__
+  #ifdef __linux__
+       ret.sigpc = ((ucontext_t*)(context))->uc_mcontext.regs->nip;
+  #endif
+#endif
 
        if (ret.sigpc == 0) {
                // Skip getSiginfo/sighandler/sigtrampgo/sigtramp/handler.