Merge pull request #8957 from slavapestov/fix-the-build-mostly

Fix the build mostly

Author: slavapestov

lib/AST/SubstitutionMap.cpp

@@ -76,7 +76,9 @@ addSubstitution(CanSubstitutableType type, Type replacement) {
 }
 
 Optional<ProtocolConformanceRef>
-SubstitutionMap::lookupConformance(CanType type, ProtocolDecl *proto) const {
+SubstitutionMap::lookupConformance(CanType origType, ProtocolDecl *proto) const {
+  CanType type = origType;
+
   // If we have an archetype, map out of the context so we can compute a
   // conformance access path.
   GenericEnvironment *genericEnv = nullptr;
@@ -146,7 +148,7 @@ SubstitutionMap::lookupConformance(CanType type, ProtocolDecl *proto) const {
       // FIXME: Rip this out once we can get a concrete conformance from
       // an archetype.
       auto *M = proto->getParentModule();
-      auto substType = type.subst(*this);
+      auto substType = origType.subst(*this);
       if (substType &&
           !substType->is<ArchetypeType>() &&
           !substType->isTypeParameter() &&
@@ -396,8 +398,13 @@ void SubstitutionMap::verify() const {
 }
 
 void SubstitutionMap::dump(llvm::raw_ostream &out) const {
+  auto *genericSig = getGenericSignature();
+  if (genericSig == nullptr) {
+    out << "Empty substitution map\n";
+    return;
+  }
   out << "Generic signature: ";
-  getGenericSignature()->print(out);
+  genericSig->print(out);
   out << "\n";
   out << "Substitutions:\n";
   for (const auto &sub : subMap) {

validation-test/execution/crashers/rdar18157434.swift

@@ -17,5 +17,12 @@ struct X<T> {
   var a: S
 }
 
-X<()>()
+func generic<T>(_: T) {}
 
+// We don't want the metadata allocation to be optimized away
+@_semantics("optimize.sil.never")
+func main() {
+  generic(X<()>())
+}
+
+main()