gc: fix select line number

Fixes #1393.

R=ken2
CC=golang-dev
https://golang.org/cl/4811054

diff --git a/src/cmd/gc/go.y b/src/cmd/gc/go.y
index d3e363d370791339cad06a0566b07f2b7d108e8d..ce1d4f5f58bb3a605cbe5ece25040de4e363104f 100644 (file)
--- a/src/cmd/gc/go.y
+++ b/src/cmd/gc/go.y
@@ -685,6 +685,7 @@ select_stmt:
        LBODY caseblock_list '}'
        {
                $$ = nod(OSELECT, N, N);
+               $$->lineno = typesw->lineno;
                $$->list = $4;
                typesw = typesw->left;
        }

diff --git a/src/cmd/gc/select.c b/src/cmd/gc/select.c
index 095c764159d09bcbaf18baeaa0774b9c449133de..8395dda319595cf82d4a5108fc3fb5bae264a14a 100644 (file)
--- a/src/cmd/gc/select.c
+++ b/src/cmd/gc/select.c
@@ -108,6 +108,7 @@ walkselect(Node *sel)
        // optimization: one-case select: single op.
        if(i == 1) {
                cas = sel->list->n;
+               setlineno(cas);
                l = cas->ninit;
                if(cas->left != N) {  // not default:
                        n = cas->left;
@@ -165,6 +166,7 @@ walkselect(Node *sel)
        // this rewrite is used by both the general code and the next optimization.
        for(l=sel->list; l; l=l->next) {
                cas = l->n;
+               setlineno(cas);
                n = cas->left;
                if(n == N)
                        continue;
@@ -238,6 +240,7 @@ walkselect(Node *sel)
                }
                
                n = cas->left;
+               setlineno(n);
                r = nod(OIF, N, N);
                r->ninit = cas->ninit;
                switch(n->op) {
@@ -283,6 +286,7 @@ walkselect(Node *sel)
        sel->ninit = nil;
 
        // generate sel-struct
+       setlineno(sel);
        var = nod(OXXX, N, N);
        tempname(var, ptrto(types[TUINT8]));
        r = nod(OAS, var, mkcall("newselect", var->type, nil, nodintconst(sel->xoffset)));
@@ -292,6 +296,7 @@ walkselect(Node *sel)
        // register cases
        for(l=sel->list; l; l=l->next) {
                cas = l->n;
+               setlineno(cas);
                n = cas->left;
                r = nod(OIF, N, N);
                r->nbody = cas->ninit;
@@ -338,6 +343,7 @@ walkselect(Node *sel)
        }
 
        // run the select
+       setlineno(sel);
        init = list(init, mkcall("selectgo", T, nil, var));
        sel->nbody = init;
 

diff --git a/test/fixedbugs/bug347.go b/test/fixedbugs/bug347.go
new file mode 100644 (file)
index 0000000..5532cee
--- /dev/null
+++ b/test/fixedbugs/bug347.go
@@ -0,0 +1,49 @@
+// $G $D/$F.go && $L $F.$A && ./$A.out
+
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+       "runtime"
+       "strings"
+)
+
+var t *struct {
+       c chan int
+}
+
+var c chan int
+
+func f() {
+       select {
+       case <-t.c:  // THIS IS LINE 22
+               break
+       case <-c:
+               break
+       }
+}
+
+func main() {
+       defer func() {
+               recover()
+               for i := 0;; i++ {
+                       pc, file, line, ok := runtime.Caller(i)
+                       if !ok {
+                               print("BUG: bug347: cannot find caller\n")
+                               return
+                       }
+                       if !strings.Contains(file, "bug347.go") || runtime.FuncForPC(pc).Name() != "main.f" {
+                               // walk past runtime frames
+                               continue
+                       }
+                       if line != 22 {
+                               print("BUG: bug347: panic at ", file, ":", line, " in ", runtime.FuncForPC(pc).Name(), "\n")
+                       }
+                       return
+               }
+       }()
+       f()
+}