libgo patch committed: Skip runtime functions with no name in runtime/pprof

[Ian Lance Taylor]

GCC PR 65797 causes some of the runtime functions to be compiled with
no name in the debug info.  This in turn causes the runtime/pprof test
to fail as reported in GCC PR 64683.

There are no good choices when a function has no name in the debug
info, but this patch assumes that if we see such a function while
reading the runtime functions, we assume that it is also a runtime
function.

Bootstrapped and ran Go testsuite on x86_64-unknown-linux-gnu.
Committed to mainline and GCC 5 branch.

Ian

diff -r df28882adbdf libgo/go/runtime/pprof/pprof.go
--- a/libgo/go/runtime/pprof/pprof.go   Fri Apr 17 12:28:57 2015 -0700
+++ b/libgo/go/runtime/pprof/pprof.go   Fri Apr 17 14:24:43 2015 -0700
@@ -351,6 +351,10 @@
                        if !show && !strings.Contains(name, ".") && 
strings.HasPrefix(name, "__go_") {
                                continue
                        }
+                       if !show && name == "" {
+                               // This can happen due to 
http://gcc.gnu.org/PR65797.
+                               continue
+                       }
                        show = true
                        fmt.Fprintf(w, "#\t%#x\t%s+%#x\t%s:%d\n", pc, name, 
pc-f.Entry(), file, line)
                }