2 files changed, 15 insertions, 7 deletions
diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go
index 2ba1ddbb44..96351def6e 100644
--- a/src/cmd/compile/internal/gc/ssa.go
+++ b/src/cmd/compile/internal/gc/ssa.go
@@ -108,17 +108,18 @@ func buildssa(fn *Node) (ssafn *ssa.Func, usessa bool) {
 	// Link up variable uses to variable definitions
 	s.linkForwardReferences()
 
-	// Main call to ssa package to compile function
-	ssa.Compile(s.f)
-
 	// Calculate stats about what percentage of functions SSA handles.
 	if false {
-		fmt.Printf("SSA implemented: %t\n", !e.unimplemented)
+		defer func() { fmt.Printf("SSA implemented: %t\n", !e.unimplemented) }()
 	}
 
 	if e.unimplemented {
 		return nil, false
 	}
+
+	// Main call to ssa package to compile function.
+	ssa.Compile(s.f)
+
 	return s.f, usessa // TODO: return s.f, true once runtime support is in (gc maps, write barriers, etc.)
 }
 
diff --git a/src/cmd/compile/internal/ssa/print.go b/src/cmd/compile/internal/ssa/print.go
index c8b90c6f93..e46590224d 100644
--- a/src/cmd/compile/internal/ssa/print.go
+++ b/src/cmd/compile/internal/ssa/print.go
@@ -8,6 +8,7 @@ import (
 	"bytes"
 	"fmt"
 	"io"
+	"os"
 )
 
 func printFunc(f *Func) {
@@ -68,16 +69,22 @@ func fprintFunc(w io.Writer, f *Func) {
 				n++
 			}
 			if m == n {
-				fmt.Fprintln(w, "dependency cycle!")
+				fmt.Fprintln(os.Stderr, "dependency cycle in block", b)
 				for _, v := range b.Values {
 					if printed[v.ID] {
 						continue
 					}
-					fmt.Fprint(w, "    ")
-					fmt.Fprintln(w, v.LongString())
+					fmt.Fprintf(os.Stderr, "    %v\n", v.LongString())
 					printed[v.ID] = true
 					n++
 				}
+				// Things are going to go very badly from here;
+				// one of the optimization passes is likely to hang.
+				// Frustratingly, panics here get swallowed by fmt,
+				// and just we end up here again if we call Fatalf.
+				// Use our last resort.
+				os.Exit(1)
+				return
 			}
 		}