change line pragma from

	//line number file
to
	//line file:number

R=rsc
CC=golang-dev
https://golang.org/cl/1868041

src/cmd/gc/lex.c

@@ -1110,7 +1110,7 @@ caseout:
 
 /*
  * read and interpret syntax that looks like
- * //line 15 parse.y
+ * //line parse.y:15
  * as a discontenuity in sequential line numbers.
  * the next line of input comes from parse.y:15
  */
@@ -1124,44 +1124,45 @@ getlinepragma(void)
 	for(i=0; i<5; i++) {
 		c = getr();
 		if(c != "line "[i])
-			return c;
+			goto out;
 	}
 
-	n = 0;
-	for(;;) {
-		c = getr();
-		if(!isdigit(c))
-			break;
-		n = n*10 + (c-'0');
-	}
-
-	if(c != ' ' || n == 0)
-		return c;
-
 	cp = lexbuf;
 	ep = lexbuf+sizeof(lexbuf)-5;
 	for(;;) {
 		c = getr();
+		if(c == '\n' || c == EOF)
+			goto out;
 		if(c == ' ')
 			continue;
-		if(c == '\n')
+		if(c == ':')
 			break;
+		if(cp < ep)
 			*cp++ = c;
-		if(cp >= ep)
-			break;
 	}
 	*cp = 0;
-//	n--;	// weve already seen the newline
-	if(n > 0) {
+
+	n = 0;
+	for(;;) {
+		c = getr();
+		if(!isdigit(c))
+			break;
+		n = n*10 + (c-'0');
+	}
+
+	if(c != '\n' || n <= 0)
+		goto out;
+
 	// try to avoid allocating file name over and over
 	for(h=hist; h!=H; h=h->link) {
 		if(h->name != nil && strcmp(h->name, lexbuf) == 0) {
 			linehist(h->name, n, 0);
-				return c;
+			goto out;
 		}
 	}
 	linehist(strdup(lexbuf), n, 0);
-	}
+
+out:
 	return c;
 }
 

src/cmd/goyacc/goyacc.go

@@ -675,7 +675,7 @@ outer:
 	//
 	if t == MARK {
 		if !lflag {
-			fmt.Fprintf(ftable, "\n//line %v %v\n", lineno, infile)
+			fmt.Fprintf(ftable, "\n//line %v:%v\n", infile, lineno)
 		}
 		for {
 			c := getrune(finput)
@@ -1032,7 +1032,7 @@ func chfind(t int, s string) int {
 func cpyunion() {
 
 	if !lflag {
-		fmt.Fprintf(ftable, "\n//line %v %v\n", lineno, infile)
+		fmt.Fprintf(ftable, "\n//line %v:%v\n", infile, lineno)
 	}
 	fmt.Fprintf(ftable, "type\tyySymType\tstruct")
 
@@ -1075,7 +1075,7 @@ func cpycode() {
 		lineno++
 	}
 	if !lflag {
-		fmt.Fprintf(ftable, "\n//line %v %v\n", lineno, infile)
+		fmt.Fprintf(ftable, "\n//line %v:%v\n", infile, lineno)
 	}
 	for c != EOF {
 		if c == '%' {
@@ -1158,7 +1158,7 @@ func dumpprod(curprod []int, max int) {
 func cpyact(curprod []int, max int) {
 
 	if !lflag {
-		fmt.Fprintf(fcode, "\n//line %v %v\n", lineno, infile)
+		fmt.Fprintf(fcode, "\n//line %v:%v\n", infile, lineno)
 	}
 
 	lno := lineno
@@ -2066,7 +2066,7 @@ nextk:
 func output() {
 	var c, u, v int
 
-	fmt.Fprintf(ftable, "\n//line 1 yacctab\n")
+	fmt.Fprintf(ftable, "\n//line yacctab:1\n")
 	fmt.Fprintf(ftable, "var\tyyExca = []int {\n")
 
 	noset := mkset()
@@ -2827,7 +2827,7 @@ func others() {
 	}
 
 	// copy yaccpar
-	fmt.Fprintf(ftable, "\n//line 1 yaccpar\n")
+	fmt.Fprintf(ftable, "\n//line yaccpar:1\n")
 
 	parts := strings.Split(yaccpar, "yyrun()", 2)
 	fmt.Fprintf(ftable, "%v", parts[0])