Implement support for module requirements, which indicate the language
features needed for a particular module to be available. This allows
mixed-language modules, where certain headers only work under some
language variants (e.g., in C++, std.tuple might only be available in
C++11 mode).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@147387 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/FrontendActions.cpp b/lib/Frontend/FrontendActions.cpp
index a97a32b..dd98fcf 100644
--- a/lib/Frontend/FrontendActions.cpp
+++ b/lib/Frontend/FrontendActions.cpp
@@ -136,6 +136,10 @@
static void collectModuleHeaderIncludes(const LangOptions &LangOpts,
clang::Module *Module,
llvm::SmallString<256> &Includes) {
+ // Don't collect any headers for unavailable modules.
+ if (!Module->isAvailable())
+ return;
+
// Add includes for each of these headers.
for (unsigned I = 0, N = Module->Headers.size(); I != N; ++I) {
if (LangOpts.ObjC1)
@@ -222,7 +226,17 @@
return false;
}
-
+
+ // Check whether we can build this module at all.
+ StringRef Feature;
+ if (!Module->isAvailable(CI.getLangOpts(), Feature)) {
+ CI.getDiagnostics().Report(diag::err_module_unavailable)
+ << Module->getFullModuleName()
+ << Feature;
+
+ return false;
+ }
+
// Do we have an umbrella header for this module?
const FileEntry *UmbrellaHeader = Module->getUmbrellaHeader();