[modules] Stop trying to fake up a linear MacroDirective history.

Modules builds fundamentally have a non-linear macro history. In the interest
of better source fidelity, represent the macro definition information
faithfully: we have a linear macro directive history within each module, and at
any point we have a unique "latest" local macro directive and a collection of
visible imported directives. This also removes the attendent complexity of
attempting to create a correct MacroDirective history (which we got wrong
in the general case).

No functionality change intended.

llvm-svn: 236176

1 files changed, 3 insertions, 3 deletions

diff --git a/clang/lib/Frontend/PrintPreprocessedOutput.cpp b/clang/lib/Frontend/PrintPreprocessedOutput.cpp
index a2737d5f370..b5e5d0aa037 100644
--- a/clang/lib/Frontend/PrintPreprocessedOutput.cpp
+++ b/clang/lib/Frontend/PrintPreprocessedOutput.cpp
@@ -686,9 +686,9 @@ static void DoPrintMacros(Preprocessor &PP, raw_ostream *OS) {
   SmallVector<id_macro_pair, 128> MacrosByID;
   for (Preprocessor::macro_iterator I = PP.macro_begin(), E = PP.macro_end();
        I != E; ++I) {
-    if (I->first->hasMacroDefinition())
-      MacrosByID.push_back(
-          id_macro_pair(I->first, I->second.getLatest()->getMacroInfo()));
+    auto *MD = I->second.getLatest();
+    if (MD && MD->isDefined())
+      MacrosByID.push_back(id_macro_pair(I->first, MD->getMacroInfo()));
   }
   llvm::array_pod_sort(MacrosByID.begin(), MacrosByID.end(), MacroIDCompare);