Make hex scanning warn on "\x{x}" and "\xx".

"\x" and and hex("x") are still valid.

p4raw-id: //depot/perl@7746

1 files changed, 11 insertions, 6 deletions

diff --git a/util.c b/util.c
index 2168d55ee6..02d0ed52f5 100644
--- a/util.c
+++ b/util.c
@@ -3094,10 +3094,20 @@ Perl_scan_hex(pTHX_ char *start, STRLEN len, STRLEN *retlen)
     register char *s = start;
     register NV rnv = 0.0;
     register UV ruv = 0;
-    register bool seenx = FALSE;
     register bool overflowed = FALSE;
     char *hexdigit;
 
+    if (len > 2) {
+	if (s[0] == 'x') {
+	    s++;
+	    len--;
+	}
+	else if (len > 3 && s[0] == '0' && s[1] == 'x') {
+	    s+=2;
+	    len-=2;
+	}
+    }
+
     for (; len-- && *s; s++) {
 	hexdigit = strchr((char *) PL_hexdigit, *s);
 	if (!hexdigit) {
@@ -3107,11 +3117,6 @@ Perl_scan_hex(pTHX_ char *start, STRLEN len, STRLEN *retlen)
 		--len;
 		++s;
 	    }
-	    else if (seenx == FALSE && *s == 'x' && ruv == 0) {
-		/* Disallow 0xxx0x0xxx... */
-		seenx = TRUE;
-		continue;
-	    }
 	    else {
 		dTHR;
 		if (ckWARN(WARN_DIGIT))