-Wc++98-compat warnings for the lexer.

This also adds a -Wc++98-compat-pedantic for warning on constructs which would
be diagnosed by -std=c++98 -pedantic (that is, it warns even on C++11 features
which we enable by default, with no warning, in C++98 mode).


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@142034 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/SemaCXX/cxx98-compat-pedantic.cpp b/test/SemaCXX/cxx98-compat-pedantic.cpp
new file mode 100644
index 0000000..2ca0ae4
--- /dev/null
+++ b/test/SemaCXX/cxx98-compat-pedantic.cpp
@@ -0,0 +1,11 @@
+// RUN: %clang_cc1 -fsyntax-only -std=c++11 -Wc++98-compat-pedantic -verify %s
+// RUN: %clang_cc1 -fsyntax-only -std=c++98 -Werror %s
+
+// -Wc++98-compat-pedantic warns on C++11 features which we accept without a
+// warning in C++98 mode.
+
+#line 32767 // ok
+#line 32768 // expected-warning {{#line number greater than 32767 is incompatible with C++98}}
+
+#define VA_MACRO(x, ...) x // expected-warning {{variadic macros are incompatible with C++98}}
+VA_MACRO(,x) // expected-warning {{empty macro argument list is incompatible with C++98}}