[clang] 269bc3f - PR47138: Don't crash if the preferred alignment of an invalid record

[Richard Smith via cfe-commits]

Author: Richard Smith
Date: 2020-08-12T12:31:20-07:00
New Revision: 269bc3f5df6c3b75de515a48063c6941ef8fbbe6

URL: https://github.com/llvm/llvm-project/commit/269bc3f5df6c3b75de515a48063c6941ef8fbbe6
DIFF: https://github.com/llvm/llvm-project/commit/269bc3f5df6c3b75de515a48063c6941ef8fbbe6.diff

LOG: PR47138: Don't crash if the preferred alignment of an invalid record
type is requested.

Added: 
    

Modified: 
    clang/lib/AST/ASTContext.cpp
    clang/test/SemaCXX/alignof.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 4d708d57cabf..544bbb5b0740 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -2457,7 +2457,7 @@ unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
     return ABIAlign;
 
   if (const auto *RT = T->getAs<RecordType>()) {
-    if (TI.AlignIsRequired)
+    if (TI.AlignIsRequired || RT->getDecl()->isInvalidDecl())
       return ABIAlign;
 
     unsigned PreferredAlign = static_cast<unsigned>(

diff  --git a/clang/test/SemaCXX/alignof.cpp b/clang/test/SemaCXX/alignof.cpp
index f2854024da1a..64986d3103e1 100644
--- a/clang/test/SemaCXX/alignof.cpp
+++ b/clang/test/SemaCXX/alignof.cpp
@@ -102,3 +102,8 @@ typedef int __attribute__((aligned(16))) aligned_int;
 template <typename>
 using template_alias = aligned_int;
 static_assert(alignof(template_alias<void>) == 16, "Expected alignment of 16" );
+
+struct PR47138 {
+  invalid_type a; // expected-error {{unknown type}}
+};
+static_assert(__alignof__(PR47138) == 1, ""); // Don't crash.