[ASTUnit] Fix crash when trying to load a module file via ASTUnit::LoadFromASTFile.

rdar://19997358

llvm-svn: 231060

clang/lib/Frontend/ASTUnit.cpp

@@ -714,6 +714,13 @@ std::unique_ptr<ASTUnit> ASTUnit::LoadFromASTFile(
       *AST->PP, Context, AST->ASTFileLangOpts, AST->TargetOpts, AST->Target,
       Counter));
 
+  // Attach the AST reader to the AST context as an external AST
+  // source, so that declarations will be deserialized from the
+  // AST file as needed.
+  // We need the external source to be set up before we read the AST, because
+  // eagerly-deserialized declarations may use it.
+  Context.setExternalSource(AST->Reader);
+
   switch (AST->Reader->ReadAST(Filename, serialization::MK_MainFile,
                           SourceLocation(), ASTReader::ARR_None)) {
   case ASTReader::Success:
@@ -733,11 +740,6 @@ std::unique_ptr<ASTUnit> ASTUnit::LoadFromASTFile(
 
   PP.setCounterValue(Counter);
 
-  // Attach the AST reader to the AST context as an external AST
-  // source, so that declarations will be deserialized from the
-  // AST file as needed.
-  Context.setExternalSource(AST->Reader);
-
   // Create an AST consumer, even though it isn't used.
   AST->Consumer.reset(new ASTConsumer);
   

clang/test/Index/index-module.m

@@ -49,6 +49,11 @@ int glob;
 // CHECK-TMOD-NEXT: [indexDeclaration]: kind: objc-class-method | name: alloc | {{.*}} | loc: [[TMOD_MODULE_H]]:17:1
 // CHECK-TMOD-NEXT: [importedASTFile]: [[PCM:.*\.cache/Module\.pcm]] | loc: [[TMOD_MODULE_H]]:23:2 | name: "Module.Sub" | isImplicit: 1
 // CHECK-TMOD-NEXT: [importedASTFile]: [[PCM]] | loc: [[TMOD_MODULE_H]]:24:2 | name: "Module.Buried.Treasure" | isImplicit: 1
+// CHECK-TMOD-NEXT: [indexDeclaration]: kind: typedef | name: FILE | {{.*}} | loc: [[TMOD_MODULE_H]]:30:3
+// CHECK-TMOD-NEXT: [indexDeclaration]: kind: struct | name: __sFILE | {{.*}} | loc: [[TMOD_MODULE_H]]:28:16
+// CHECK-TMOD-NEXT: [indexDeclaration]: kind: field | name: _offset | {{.*}} | loc: [[TMOD_MODULE_H]]:29:7
+// CHECK-TMOD-NEXT: [indexDeclaration]: kind: variable | name: myFile | {{.*}} | loc: [[TMOD_MODULE_H]]:32:14
+// CHECK-TMOD-NEXT: [indexEntityReference]: kind: typedef | name: FILE | {{.*}} | loc: [[TMOD_MODULE_H]]:32:8
 // CHECK-TMOD-NEXT: [importedASTFile]: [[PCM]] | loc: [[TMODHDR]]Sub.h:1:2 | name: "Module.Sub2" | isImplicit: 1
 // CHECK-TMOD-NEXT: [indexDeclaration]: kind: variable | name: Module_Sub | {{.*}} | loc: [[TMODHDR]]Sub.h:2:6
 // CHECK-TMOD-NEXT: [indexDeclaration]: kind: variable | name: Module_Sub2 | USR: c:@Module_Sub2 | {{.*}} | loc: [[TMODHDR]]Sub2.h:1:6

clang/test/Modules/Inputs/Module.framework/Headers/Module.h

@@ -25,4 +25,10 @@ const char *getModuleVersion(void);
 
 __asm("foo");
 
+typedef	struct __sFILE {
+  int _offset;
+} FILE;
+
+extern FILE *myFile;
+
 #endif // MODULE_H