Fix -E mismatch; an identifier followed by a numeric constant does not
require a space (to avoid concatenation) if the numeric constant had a
leading period.
 - PR3819.

llvm-svn: 67163
diff --git a/clang/test/Lexer/token-concat.c b/clang/test/Lexer/token-concat.c
new file mode 100644
index 0000000..003344f
--- /dev/null
+++ b/clang/test/Lexer/token-concat.c
@@ -0,0 +1,4 @@
+// RUN: clang -E -x c -o %t %s &&
+// RUN: grep 'IDENT.2' %t
+
+IDENT.2