Author: Sven van Haastregt Date: 2021-01-05T11:51:10Z New Revision: 0e4d2361b817bd16f97cd45d5792017edc3891ee
URL: https://github.com/llvm/llvm-project/commit/0e4d2361b817bd16f97cd45d5792017edc3891ee DIFF: https://github.com/llvm/llvm-project/commit/0e4d2361b817bd16f97cd45d5792017edc3891ee.diff LOG: [OpenCL] Warn about side effects for unevaluated vec_step arg The argument to the `vec_step` builtin is not evaluated. Hoist the diagnostic for this in `Sema::CheckUnaryExprOrTypeTraitOperand` such that it comes before `Sema::CheckVecStepTraitOperandType`. A minor side-effect of this change is that it also produces the warning for `co_await` and `co_yield` as `sizeof` arguments now, which seems to be reasonable given that the warning is emitted for `typeid` already. Differential Revision: https://reviews.llvm.org/D91348 Added: Modified: clang/lib/Sema/SemaExpr.cpp clang/test/SemaCXX/coroutines.cpp clang/test/SemaOpenCL/vec_step.cl Removed: ################################################################################ diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index 28f4c5bbf19b..d8bfd3f8b46a 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -4089,7 +4089,7 @@ bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E, bool IsUnevaluatedOperand = (ExprKind == UETT_SizeOf || ExprKind == UETT_AlignOf || - ExprKind == UETT_PreferredAlignOf); + ExprKind == UETT_PreferredAlignOf || ExprKind == UETT_VecStep); if (IsUnevaluatedOperand) { ExprResult Result = CheckUnevaluatedOperand(E); if (Result.isInvalid()) @@ -4097,6 +4097,16 @@ bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E, E = Result.get(); } + // The operand for sizeof and alignof is in an unevaluated expression context, + // so side effects could result in unintended consequences. + // Exclude instantiation-dependent expressions, because 'sizeof' is sometimes + // used to build SFINAE gadgets. + // FIXME: Should we consider instantiation-dependent operands to 'alignof'? + if (IsUnevaluatedOperand && !inTemplateInstantiation() && + !E->isInstantiationDependent() && + E->HasSideEffects(Context, false)) + Diag(E->getExprLoc(), diag::warn_side_effects_unevaluated_context); + if (ExprKind == UETT_VecStep) return CheckVecStepTraitOperandType(*this, ExprTy, E->getExprLoc(), E->getSourceRange()); @@ -4133,16 +4143,6 @@ bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E, return true; } - // The operand for sizeof and alignof is in an unevaluated expression context, - // so side effects could result in unintended consequences. - // Exclude instantiation-dependent expressions, because 'sizeof' is sometimes - // used to build SFINAE gadgets. - // FIXME: Should we consider instantiation-dependent operands to 'alignof'? - if (IsUnevaluatedOperand && !inTemplateInstantiation() && - !E->isInstantiationDependent() && - E->HasSideEffects(Context, false)) - Diag(E->getExprLoc(), diag::warn_side_effects_unevaluated_context); - if (CheckObjCTraitOperandConstraints(*this, ExprTy, E->getExprLoc(), E->getSourceRange(), ExprKind)) return true; diff --git a/clang/test/SemaCXX/coroutines.cpp b/clang/test/SemaCXX/coroutines.cpp index f354b1f2a4bb..d7208f9a1010 100644 --- a/clang/test/SemaCXX/coroutines.cpp +++ b/clang/test/SemaCXX/coroutines.cpp @@ -328,6 +328,7 @@ void unevaluated() { // expected-warning@-1 {{declaration does not declare anything}} sizeof(co_await a); // expected-error {{'co_await' cannot be used in an unevaluated context}} // expected-error@-1 {{invalid application of 'sizeof' to an incomplete type 'void'}} + // expected-warning@-2 {{expression with side effects has no effect in an unevaluated context}} typeid(co_await a); // expected-error {{'co_await' cannot be used in an unevaluated context}} // expected-warning@-1 {{expression with side effects has no effect in an unevaluated context}} // expected-warning@-2 {{expression result unused}} @@ -335,6 +336,7 @@ void unevaluated() { // expected-warning@-1 {{declaration does not declare anything}} sizeof(co_yield 2); // expected-error {{'co_yield' cannot be used in an unevaluated context}} // expected-error@-1 {{invalid application of 'sizeof' to an incomplete type 'void'}} + // expected-warning@-2 {{expression with side effects has no effect in an unevaluated context}} typeid(co_yield 3); // expected-error {{'co_yield' cannot be used in an unevaluated context}} // expected-warning@-1 {{expression with side effects has no effect in an unevaluated context}} // expected-warning@-2 {{expression result unused}} diff --git a/clang/test/SemaOpenCL/vec_step.cl b/clang/test/SemaOpenCL/vec_step.cl index 0a2f6ef30e76..afb6dc94d92e 100644 --- a/clang/test/SemaOpenCL/vec_step.cl +++ b/clang/test/SemaOpenCL/vec_step.cl @@ -29,4 +29,6 @@ void foo(int3 arg1, int8 arg2) { int res13 = vec_step(*incomplete1); // expected-error {{'vec_step' requires built-in scalar or vector type, '__private struct S' invalid}} int res14 = vec_step(int16*); // expected-error {{'vec_step' requires built-in scalar or vector type, '__private int16 *' invalid}} int res15 = vec_step(void(void)); // expected-error {{'vec_step' requires built-in scalar or vector type, 'void (void)' invalid}} + + int res_no_effect = vec_step(auto3++); // expected-warning {{expression with side effects has no effect in an unevaluated context}} } _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
