Index: lib/Sema/SemaType.cpp =================================================================== --- lib/Sema/SemaType.cpp +++ lib/Sema/SemaType.cpp @@ -2082,7 +2082,7 @@ QualType Sema::BuildArrayType(QualType T, ArrayType::ArraySizeModifier ASM, Expr *ArraySize, unsigned Quals, SourceRange Brackets, DeclarationName Entity) { - + ArraySize->EvaluateForOverflow(Context); SourceLocation Loc = Brackets.getBegin(); if (getLangOpts().CPlusPlus) { // C++ [dcl.array]p1: Index: test/Sema/integer-overflow.c =================================================================== --- test/Sema/integer-overflow.c +++ test/Sema/integer-overflow.c @@ -172,6 +172,9 @@ // expected-warning@+1 {{overflow in expression; result is 536870912 with type 'int'}} (void)f2(0, f0(4608 * 1024 * 1024)); } +void check_integer_overflows_in_array_size() { + int arr[4608 * 1024 * 1024]; // expected-warning {{overflow in expression; result is 536870912 with type 'int'}} +} struct s { unsigned x;