[clang] Check for null TypeSourceInfo in Sema::CreateUnaryExprOrTypeTraitExpr

Author: sookach

clang/docs/ReleaseNotes.rst

@@ -683,6 +683,9 @@ New features
 Crash and bug fixes
 ^^^^^^^^^^^^^^^^^^^
 
+- Check for a null ``TypeSourceInfo *`` when creating a ``UnaryExprOrTypeTraitExpr``.
+  Fixes (#GH111594)
+
 Improvements
 ^^^^^^^^^^^^
 

clang/lib/Sema/SemaExpr.cpp

@@ -4629,6 +4629,9 @@ ExprResult Sema::CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo,
       TInfo->getType()->isVariablyModifiedType())
     TInfo = TransformToPotentiallyEvaluated(TInfo);
 
+  if (!TInfo)
+    return ExprError();
+
   // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t.
   return new (Context) UnaryExprOrTypeTraitExpr(
       ExprKind, TInfo, Context.getSizeType(), OpLoc, R.getEnd());

clang/test/SemaCXX/unary-expr-or-type-trait-invalid.cpp

@@ -0,0 +1,26 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+a() {struct b c (sizeof(b * [({ {tree->d* next)} 0
+
+// expected-error@3 {{a type specifier is required for all declarations}}
+// expected-error@3 {{use of undeclared identifier 'tree'; did you mean 'true'?}}
+// expected-error@3 {{member reference type 'bool' is not a pointer}}
+// expected-error@3 {{expected ';' after expression}}
+// expected-error@3 {{use of undeclared identifier 'next'; did you mean 'new'?}}
+// expected-error@3 {{expected expression}}
+// expected-error@3 {{expected ';' after expression}}
+// expected-error@26 {{expected '}'}}
+// expected-note@3 {{to match this '{'}}
+// expected-error@26 {{expected ')'}}
+// expected-note@3 {{to match this '('}}
+// expected-error@26 {{expected ']'}}
+// expected-note@3 {{to match this '['}}
+// expected-error@26 {{expected ')'}}
+// expected-note@3 {{to match this '('}}
+// expected-error@3 {{using declaration 'exp' instantiates to an empty pack}}
+// expected-error@3 {{variable has incomplete type 'struct b'}}
+// expected-note@3 {{forward declaration of 'b'}}
+// expected-error@3 {{expected ';' at end of declaration}}
+// expected-error@26 {{expected '}'}}
+// expected-note@3 {{to match this '{'}}
+// expected-warning@3 {{expression result unused}}