Features: Extend concept to C language.

Add properties and variables corresponding to CXX equivalents.

Add features for c_function_prototypes (C90), c_restrict (C99),
c_variadic_macros (C99) and c_static_assert (C11). This feature
set can be extended later.

Add a <PREFIX>_RESTRICT symbol define to WriteCompilerDetectionHeader
to conditionally represent the c_restrict feature.

1 files changed, 7 insertions, 0 deletions

diff --git a/Tests/RunCMake/CompileFeatures/empty.c b/Tests/RunCMake/CompileFeatures/empty.c
new file mode 100644
index 0000000000..bfbbddeb90
--- /dev/null
+++ b/Tests/RunCMake/CompileFeatures/empty.c
@@ -0,0 +1,7 @@
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+int empty()
+{
+  return 0;
+}