Fix for PR2750; don't check for an 'e' in the trash after the token.

Note that this isn't really a complete fix; I think there are other 
potential overrun situations.  I don't really know what the best 
systematic fix is, though.

llvm-svn: 55622

clang/lib/Lex/LiteralSupport.cpp

@@ -224,7 +224,7 @@ NumericLiteralParser(const char *begin, const char *end,
       saw_period = true;
       s = SkipDigits(s);
     } 
-    if (*s == 'e' || *s == 'E') { // exponent
+    if (s != ThisTokEnd && (*s == 'e' || *s == 'E')) { // exponent
       const char *Exponent = s;
       s++;
       saw_exponent = true;

clang/test/Lexer/numeric-literal-trash.c

@@ -0,0 +1,13 @@
+/* RUN: clang -fsyntax-only -verify %s
+ */
+# define XRECORD(x, c_name) e##c (x, __LINE__)
+
+
+
+
+
+
+ void x() {
+
+XRECORD (XRECORD (1, 1), 1);
+    }