better diagnostics for eof in a string.

this assumes that embedded newlines are
legal in back-quote strings.

R=r
OCL=30502
CL=30502

diff --git a/src/cmd/gc/lex.c b/src/cmd/gc/lex.c
index 0efa665ee94c5e0d5c86fc15c82040bc0da9c12b..2cad4310ebf461cdc658866e39fd7ccec3d01099 100644 (file)
--- a/src/cmd/gc/lex.c
+++ b/src/cmd/gc/lex.c
@@ -371,11 +371,11 @@ isfrog(int c)
 static int32
 _yylex(void)
 {
-       int c, c1, clen;
+       int c, c1, clen, escflag;
        vlong v;
        char *cp;
        Rune rune;
-       int escflag;
+       int32 lno;
        Sym *s;
 
        prevlineno = lineno;
@@ -459,9 +459,14 @@ l0:
                clen = sizeof(int32);
 
        casebq:
+               lno = lineno;
                for(;;) {
                        c = getc();
-                       if(c == EOF || c == '`')
+                       if(c == EOF) {
+                               yyerror("eof in string starting at line %L", lno);
+                               break;
+                       }
+                       if(c == '`')
                                break;
                        cp = remal(cp, clen, 1);
                        cp[clen++] = c;
@@ -1082,11 +1087,16 @@ escchar(int e, int *escflg, vlong *val)
 
 loop:
        c = getr();
-       if(c == '\n') {
+       switch(c) {
+       case EOF:
+               yyerror("eof in string");
+               return 1;
+       case '\n':
                yyerror("newline in string");
                return 1;
-       }
-       if(c != '\\') {
+       case '\\':
+               break;
+       default:
                if(c == e)
                        return 1;
                *val = c;