[Clang] Fix crash when checking misaligned member with dependent type

If the type is dependent, we should just discard it and not checking its
alignment as it doesn't exisit yet.
Fixes https://github.com/llvm/llvm-project/issues/58370

Differential Revision: https://reviews.llvm.org/D136018

diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index c0ecd7b..9d8640a 100644 (file)
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -17387,15 +17387,15 @@ void Sema::DiagnoseMisalignedMembers() {
 
 void Sema::DiscardMisalignedMemberAddress(const Type *T, Expr *E) {
   E = E->IgnoreParens();
-  if (!T->isPointerType() && !T->isIntegerType())
+  if (!T->isPointerType() && !T->isIntegerType() && !T->isDependentType())
     return;
   if (isa<UnaryOperator>(E) &&
       cast<UnaryOperator>(E)->getOpcode() == UO_AddrOf) {
     auto *Op = cast<UnaryOperator>(E)->getSubExpr()->IgnoreParens();
     if (isa<MemberExpr>(Op)) {
-      auto MA = llvm::find(MisalignedMembers, MisalignedMember(Op));
+      auto *MA = llvm::find(MisalignedMembers, MisalignedMember(Op));
       if (MA != MisalignedMembers.end() &&
-          (T->isIntegerType() ||
+          (T->isDependentType() || T->isIntegerType() ||
            (T->isPointerType() && (T->getPointeeType()->isIncompleteType() ||
                                    Context.getTypeAlignInChars(
                                        T->getPointeeType()) <= MA->Alignment))))

diff --git a/clang/test/SemaCXX/misaligned-member-with-depdent-type.cpp b/clang/test/SemaCXX/misaligned-member-with-depdent-type.cpp
new file mode 100644 (file)
index 0000000..cd47683
--- /dev/null
+++ b/clang/test/SemaCXX/misaligned-member-with-depdent-type.cpp
@@ -0,0 +1,21 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+struct __attribute__((packed)) {
+  unsigned options;
+  template <typename T>
+  void getOptions() {
+      (T *)&options;
+  }
+  template <typename U>
+       void getOptions2() {
+      (U)&options;
+       }
+} s;
+
+struct __attribute__((packed)) { // expected-error {{anonymous structs and classes must be class members}}
+           unsigned options ;
+  template <typename T> getOptions() // expected-error {{a type specifier is required for all declarations}}
+    {
+      (T *) & options;
+    }
+};