replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

[Sema] Add lvalue-to-rvalue cast in direct-list-initialization of enum 

After r264564, we allowed direct-list-initialization of an enum from an
integral value in C++1z mode, so long as that value can convert to the
enum's underlying type.

In this kind of initialization, we need a lvalue-to-rvalue conversion
for the initializer value if it is not a rvalue. This lets us accept the
following code:

  enum class A : unsigned {};
  A foo(unsigned x) { return A{x}; }

Differential Revision: https://reviews.llvm.org/D29723

llvm-svn: 295266
This commit is contained in:
Vedant Kumar 2017-02-16 01:20:00 +00:00
parent 6237678b14
commit f4217f862a
2 changed files with 33 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
clang/lib/Sema/SemaInit.cpp
View File

@ -3981,6 +3981,8 @@ static void TryListInitialization(Sema &S,
ImplicitConversionSequence ICS;
ICS.setStandard();
ICS.Standard.setAsIdentityConversion();
if (!E->isRValue())
ICS.Standard.First = ICK_Lvalue_To_Rvalue;
// If E is of a floating-point type, then the conversion is ill-formed
// due to narrowing, but go through the motions in order to produce the
// right diagnostic.

45
clang/test/CXX/dcl.decl/dcl.init/dcl.init.list/p3.cpp
View File

@ -150,35 +150,44 @@ namespace cxx1z_direct_enum_init {
void f(T);
f(T{0});
char c;
auto t3 = T{c};
}
#if __cplusplus <= 201402L
// expected-error@-15 5{{cannot initialize}}
// expected-error@-15 5{{cannot initialize}}
// expected-error@-15 5{{cannot initialize}}
// expected-error@-18 5{{cannot initialize}}
// expected-error@-18 5{{cannot initialize}}
// expected-error@-18 5{{cannot initialize}}
//
//
// expected-error@-15 5{{cannot initialize}}
// expected-error@-18 5{{cannot initialize}}
//
// expected-error@-15 5{{cannot initialize}}
// expected-error@-18 5{{cannot initialize}}
//
// expected-error@-15 5{{cannot initialize}}
// expected-error@-18 5{{cannot initialize}}
//
//
// expected-error@-15 5{{cannot initialize}}
// expected-error@-18 5{{cannot initialize}}
//
//
// expected-error@-18 5{{cannot initialize}}
#else
// expected-error@-29 {{cannot initialize}}
// expected-error@-29 {{cannot initialize}}
// expected-error@-29 {{cannot initialize}}
// expected-error@-35 {{cannot initialize}}
// expected-error@-35 {{cannot initialize}}
// expected-error@-35 {{cannot initialize}}
//
//
// expected-error@-29 {{cannot initialize}}
// expected-error@-35 {{cannot initialize}}
//
// expected-error@-29 {{cannot initialize}}
// expected-error@-35 {{cannot initialize}}
//
// expected-error@-29 {{cannot initialize}}
// expected-error@-35 {{cannot initialize}}
//
//
// expected-error@-29 {{cannot initialize}}
// expected-error@-35 {{cannot initialize}}
//
//
// expected-error@-35 {{cannot initialize}}
#endif
template<typename T> void bad() {
@ -252,4 +261,12 @@ namespace cxx1z_direct_enum_init {
(void)B{0.0}; // expected-error {{type 'double' cannot be narrowed}}
#endif
}
#if __cplusplus > 201402L
enum class F : unsigned {};
F f1(unsigned x) { return F{x}; }
F f2(const unsigned x) { return F{x}; }
F f3(bool x) { return F{x}; }
F f4(const bool x) { return F{x}; }
#endif
}