Commit f0719bf2 authored by Erich Keane's avatar Erich Keane
Browse files

PR44514: Fix recovery from noexcept with non-convertible expressions 

We currently treat noexcept(not-convertible-to-bool) as 'none', which
results in the typeloc info being a different size, and causing an
assert later on in the process.  In order to make recovery less
destructive, replace this with noexcept(false) and a constructed 'false'
expression.

Bug Report: https://bugs.llvm.org/show_bug.cgi?id=44514

Differential Revision: https://reviews.llvm.org/D72621
parent 31441a3e

clang/lib/Sema/SemaExceptionSpec.cpp

+10 −2
Original line number Diff line number Diff line
@@ -81,8 +81,16 @@ ExprResult Sema::ActOnNoexceptSpec(SourceLocation NoexceptLoc, 
                                   ExceptionSpecificationType &EST) {

  // FIXME: This is bogus, a noexcept expression is not a condition.

  ExprResult Converted = CheckBooleanCondition(NoexceptLoc, NoexceptExpr);

  if (Converted.isInvalid())

    return Converted;

  if (Converted.isInvalid()) {

    EST = EST_NoexceptFalse;



    // Fill in an expression of 'false' as a fixup.

    auto *BoolExpr = new (Context)

        CXXBoolLiteralExpr(false, Context.BoolTy, NoexceptExpr->getBeginLoc());

    llvm::APSInt Value{1};

    Value = 0;

    return ConstantExpr::Create(Context, BoolExpr, APValue{Value});

  }



  if (Converted.get()->isValueDependent()) {

    EST = EST_DependentNoexcept;

clang/test/SemaCXX/cxx0x-noexcept-expression.cpp

+5 −0
Original line number Diff line number Diff line
@@ -75,3 +75,8 @@ void vla(bool b) { 
  static_assert(!noexcept((int(*)[b ? throw : 42])0), "");

  static_assert(!noexcept((int(*)[b ? throw : 42]){0}), "");

}



struct pr_44514 {

  // expected-error@+1{{value of type 'void' is not contextually convertible to 'bool'}}

  void foo(void) const &noexcept(f());

};