Don't allow #include (and its friends #import, #include_next and

#__include_macros) in the arguments of a function-style macro. Directives in the
arguments of such macros have undefined behaviour, and GCC does not correctly
support these cases. In some situations, this can lead to better diagnostics.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@146765 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 29 insertions, 0 deletions

diff --git a/test/Preprocessor/macro_arg_directive.c b/test/Preprocessor/macro_arg_directive.c
new file mode 100644
index 0000000000..5c9943d605
--- /dev/null
+++ b/test/Preprocessor/macro_arg_directive.c
@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 %s -fsyntax-only -verify
+
+// header1.h
+void fail(const char *);
+#define MUNCH(...) \
+ ({ int result = 0; __VA_ARGS__; if (!result) { fail(#__VA_ARGS__); }; result })
+
+static inline int f(int k) {
+  return MUNCH( // expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{returning 'void'}}
+    if (k < 3)
+      result = 24;
+    else if (k > 4)
+      result = k - 4;
+}
+
+#include "macro_arg_directive.h" // expected-error {{embedding a #include directive within macro arguments is not supported}}
+
+int g(int k) {
+  return f(k) + f(k-1));
+}
diff --git a/test/Preprocessor/macro_arg_directive.h b/test/Preprocessor/macro_arg_directive.h
new file mode 100644
index 0000000000..892dbf2b13
--- /dev/null
+++ b/test/Preprocessor/macro_arg_directive.h
@@ -0,0 +1,9 @@
+// Support header for macro_arg_directive.c
+
+int n;
+
+struct S {
+  int k;
+};
+
+void g(int);