cmd/yacc: report correct line for 'default action causes potential type clash'

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/13588044

diff --git a/src/cmd/yacc/yacc.go b/src/cmd/yacc/yacc.go
index bb406f5743abbea2d9b787bdce9a0a4709bdcba0..dd4d3e69afb80873c196b817c2f1440d1b0c73f3 100644 (file)
--- a/src/cmd/yacc/yacc.go
+++ b/src/cmd/yacc/yacc.go
@@ -555,17 +555,18 @@ outer:
 
                // process a rule
                rlines[nprod] = lineno
+               ruleline := lineno
                if t == '|' {
                        curprod[mem] = prdptr[nprod-1][0]
                        mem++
                } else if t == IDENTCOLON {
                        curprod[mem] = chfind(1, tokname)
                        if curprod[mem] < NTBASE {
-                               errorf("token illegal on LHS of grammar rule")
+                               lerrorf(ruleline, "token illegal on LHS of grammar rule")
                        }
                        mem++
                } else {
-                       errorf("illegal rule: missing semicolon or | ?")
+                       lerrorf(ruleline, "illegal rule: missing semicolon or | ?")
                }
 
                // read rule body
@@ -586,11 +587,11 @@ outer:
                        }
                        if t == PREC {
                                if gettok() != IDENTIFIER {
-                                       errorf("illegal %%prec syntax")
+                                       lerrorf(ruleline, "illegal %%prec syntax")
                                }
                                j = chfind(2, tokname)
                                if j >= NTBASE {
-                                       errorf("nonterminal " + nontrst[j-NTBASE].name + " illegal after %%prec")
+                                       lerrorf(ruleline, "nonterminal "+nontrst[j-NTBASE].name+" illegal after %%prec")
                                }
                                levprd[nprod] = toklev[j]
                                t = gettok()
@@ -646,7 +647,7 @@ outer:
                        // no explicit action, LHS has value
                        tempty := curprod[1]
                        if tempty < 0 {
-                               errorf("must return a value, since LHS has a type")
+                               lerrorf(ruleline, "must return a value, since LHS has a type")
                        }
                        if tempty >= NTBASE {
                                tempty = nontrst[tempty-NTBASE].value
@@ -654,7 +655,7 @@ outer:
                                tempty = TYPE(toklev[tempty])
                        }
                        if tempty != nontrst[curprod[0]-NTBASE].value {
-                               errorf("default action causes potential type clash")
+                               lerrorf(ruleline, "default action causes potential type clash")
                        }
                        fmt.Fprintf(fcode, "\n\tcase %v:", nprod)
                        fmt.Fprintf(fcode, "\n\t\t%sVAL.%v = %sS[%spt-0].%v",
@@ -3193,7 +3194,7 @@ func create(s string) *bufio.Writer {
 //
 // write out error comment
 //
-func errorf(s string, v ...interface{}) {
+func lerrorf(lineno int, s string, v ...interface{}) {
        nerrors++
        fmt.Fprintf(stderr, s, v...)
        fmt.Fprintf(stderr, ": %v:%v\n", infile, lineno)
@@ -3203,6 +3204,10 @@ func errorf(s string, v ...interface{}) {
        }
 }
 
+func errorf(s string, v ...interface{}) {
+       lerrorf(lineno, s, v...)
+}
+
 func exit(status int) {
        if ftable != nil {
                ftable.Flush()