Fix crashes from delayed template parsing code that assumed getBody() would return non-null.

Patch by Etienne Bergeron.

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@264049 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 71 insertions, 8 deletions

diff --git a/clang-tidy/cppcoreguidelines-pro-type-member-init-delayed.cpp b/clang-tidy/cppcoreguidelines-pro-type-member-init-delayed.cpp
new file mode 100644
index 00000000..356aa007
--- /dev/null
+++ b/clang-tidy/cppcoreguidelines-pro-type-member-init-delayed.cpp
@@ -0,0 +1,32 @@
+// RUN: %check_clang_tidy %s cppcoreguidelines-pro-type-member-init %t -- -- -fdelayed-template-parsing
+
+template<class T>
+struct PositiveFieldBeforeConstructor {
+  PositiveFieldBeforeConstructor() {}
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: constructor does not initialize these built-in/pointer fields: F, G, H
+  int F;
+  bool G /* with comment */;
+  int *H;
+};
+// Explicit instantiation.
+template class PositiveFieldBeforeConstructor<int>;
+
+template<class T>
+struct PositiveFieldAfterConstructor {
+  PositiveFieldAfterConstructor() {}
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: constructor does not initialize these built-in/pointer fields: F, G, H
+  int F;
+  bool G /* with comment */;
+  int *H;
+};
+// Explicit instantiation.
+template class PositiveFieldAfterConstructor<int>;
+
+// This declaration isn't used and won't be parsed 'delayed-template-parsing'.
+// The body of the declaration is 'null' and may cause crash if not handled
+// properly by checkers.
+template<class T>
+struct UnusedDelayedConstructor {
+  UnusedDelayedConstructor() {}
+  int F;
+};
diff --git a/clang-tidy/cppcoreguidelines/ProTypeMemberInitCheck.cpp b/clang-tidy/cppcoreguidelines/ProTypeMemberInitCheck.cpp
index 6e5896a9..672d222e 100644
--- a/clang-tidy/cppcoreguidelines/ProTypeMemberInitCheck.cpp
+++ b/clang-tidy/cppcoreguidelines/ProTypeMemberInitCheck.cpp
@@ -179,6 +179,11 @@ void ProTypeMemberInitCheck::check(const MatchFinder::MatchResult &Result) {
   const auto *Ctor = Result.Nodes.getNodeAs<CXXConstructorDecl>("ctor");
   const auto &MemberFields = Ctor->getParent()->fields();
 
+  // Skip declarations delayed by late template parsing without a body.
+  const Stmt *Body = Ctor->getBody();
+  if (!Body)
+    return;
+
   SmallPtrSet<const FieldDecl *, 16> FieldsToInit;
   fieldsRequiringInit(MemberFields, FieldsToInit);
   if (FieldsToInit.empty())
@@ -193,8 +198,8 @@ void ProTypeMemberInitCheck::check(const MatchFinder::MatchResult &Result) {
       continue;
     FieldsToInit.erase(Init->getMember());
   }
-  removeFieldsInitializedInBody(*Ctor->getBody(), *Result.Context,
-                                FieldsToInit);
+  removeFieldsInitializedInBody(*Body, *Result.Context, FieldsToInit);
+
   if (FieldsToInit.empty())
     return;
 
diff --git a/clang-tidy/modernize-redundant-void-arg-delayed.cpp b/clang-tidy/modernize-redundant-void-arg-delayed.cpp
new file mode 100644
index 00000000..dd887758
--- /dev/null
+++ b/clang-tidy/modernize-redundant-void-arg-delayed.cpp
@@ -0,0 +1,28 @@
+// RUN: %check_clang_tidy %s modernize-redundant-void-arg %t -- -- -fdelayed-template-parsing
+
+int foo(void) {
+// CHECK-MESSAGES: :[[@LINE-1]]:9: warning: redundant void argument list in function definition [modernize-redundant-void-arg]
+// CHECK-FIXES: {{^}}int foo() {{{$}}
+    return 0;
+}
+
+template <class T>
+struct MyFoo {
+  int foo(void) {
+// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: redundant void argument list in function definition [modernize-redundant-void-arg]
+// CHECK-FIXES: {{^}}  int foo() {{{$}}
+    return 0;
+  }
+};
+// Explicit instantiation.
+template class MyFoo<int>;
+
+template <class T>
+struct MyBar {
+  // This declaration isn't instantiated and won't be parsed 'delayed-template-parsing'.
+  int foo(void) {
+// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: redundant void argument list in function definition [modernize-redundant-void-arg]
+// CHECK-FIXES: {{^}}  int foo() {{{$}}
+    return 0;
+  }
+};
diff --git a/clang-tidy/modernize/RedundantVoidArgCheck.cpp b/clang-tidy/modernize/RedundantVoidArgCheck.cpp
index 4c8f681b..eb971a91 100644
--- a/clang-tidy/modernize/RedundantVoidArgCheck.cpp
+++ b/clang-tidy/modernize/RedundantVoidArgCheck.cpp
@@ -102,13 +102,11 @@ void RedundantVoidArgCheck::check(const MatchFinder::MatchResult &Result) {
 
 void RedundantVoidArgCheck::processFunctionDecl(
     const MatchFinder::MatchResult &Result, const FunctionDecl *Function) {
-  SourceLocation Start = Function->getLocStart();
   if (Function->isThisDeclarationADefinition()) {
-    SourceLocation End;
-    if (Function->hasBody())
-      End = Function->getBody()->getLocStart().getLocWithOffset(-1);
-    else
-      End = Function->getLocEnd();
+    const Stmt *Body = Function->getBody();
+    SourceLocation Start = Function->getLocStart();
+    SourceLocation End = Body ? Body->getLocStart().getLocWithOffset(-1) :
+                                Function->getLocEnd();
     removeVoidArgumentTokens(Result, SourceRange(Start, End),
                              "function definition");
   } else {