Improve diagnostic to tell you a type is incomplete.

I recently ran into this code:
```
\#include <iostream>
void foo(const std::string &s, const std::string& = "");
\#include <string>
void test() { foo(""); }
```

The diagnostic produced said it can't bind char[1] to std::string
const&. It didn't mention std::string is incomplete. The user had to
infer that.

This patch causes the diagnostic to now say "incomplete type".

llvm-svn: 352927
This commit is contained in:
Eric Fiselier 2019-02-01 22:06:02 +00:00
parent 2e719bc428
commit 1147f71fed
4 changed files with 14 additions and 3 deletions

View File

@ -1828,8 +1828,9 @@ def err_reference_bind_drops_quals : Error<
"'volatile'|'const' and 'volatile'|'restrict' and 'volatile'|" "'volatile'|'const' and 'volatile'|'restrict' and 'volatile'|"
"'const', 'restrict', and 'volatile'}2 qualifier%plural{1:|2:|4:|:s}2">; "'const', 'restrict', and 'volatile'}2 qualifier%plural{1:|2:|4:|:s}2">;
def err_reference_bind_failed : Error< def err_reference_bind_failed : Error<
"reference %diff{to type $ could not bind to an %select{rvalue|lvalue}1 of " "reference %diff{to %select{type|incomplete type}1 $ could not bind to an "
"type $|could not bind to %select{rvalue|lvalue}1 of incompatible type}0,2">; "%select{rvalue|lvalue}2 of type $|could not bind to %select{rvalue|lvalue}2 of "
"incompatible type}0,3">;
def err_reference_bind_init_list : Error< def err_reference_bind_init_list : Error<
"reference to type %0 cannot bind to an initializer list">; "reference to type %0 cannot bind to an initializer list">;
def err_init_list_bad_dest_type : Error< def err_init_list_bad_dest_type : Error<

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@ -8450,6 +8450,7 @@ bool InitializationSequence::Diagnose(Sema &S,
case FK_ReferenceInitFailed: case FK_ReferenceInitFailed:
S.Diag(Kind.getLocation(), diag::err_reference_bind_failed) S.Diag(Kind.getLocation(), diag::err_reference_bind_failed)
<< DestType.getNonReferenceType() << DestType.getNonReferenceType()
<< DestType.getNonReferenceType()->isIncompleteType()
<< OnlyArg->isLValue() << OnlyArg->isLValue()
<< OnlyArg->getType() << OnlyArg->getType()
<< Args[0]->getSourceRange(); << Args[0]->getSourceRange();

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@ -327,7 +327,7 @@ namespace update_rbrace_loc_crash {
struct A {}; struct A {};
template <typename T, typename F, int... I> template <typename T, typename F, int... I>
std::initializer_list<T> ExplodeImpl(F p1, A<int, I...>) { std::initializer_list<T> ExplodeImpl(F p1, A<int, I...>) {
// expected-error@+1 {{reference to type 'const update_rbrace_loc_crash::Incomplete' could not bind to an rvalue of type 'void'}} // expected-error@+1 {{reference to incomplete type 'const update_rbrace_loc_crash::Incomplete' could not bind to an rvalue of type 'void'}}
return {p1(I)...}; return {p1(I)...};
} }
template <typename T, int N, typename F> template <typename T, int N, typename F>

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@ -36,3 +36,12 @@ namespace PR16502 {
int f(); int f();
const A &c = { 10, ++c.temporary }; const A &c = { 10, ++c.temporary };
} }
namespace IncompleteTest {
struct String;
// expected-error@+1 {{reference to incomplete type 'const IncompleteTest::String' could not bind to an lvalue of type 'const char [1]'}}
void takeString(const String& = "") {} // expected-note {{passing argument to parameter here}} expected-note {{candidate function}}
void test() {
takeString(); // expected-error {{no matching function for call}}
}
}