[libc++] Fix PR 31938 - std::basic_string constructors use non-deductible parameter types.
Summary:
This patch fixes http://llvm.org/PR31938. The description below is copy/pasted from the bug:
The standard says:
template<class charT, class traits = char_traits<charT>,
class Allocator = allocator<charT>>
class basic_string {
using value_type = typename traits::char_type;
// ...
basic_string(const charT* s, const Allocator& a = Allocator());
};
libc++ actually chooses to declare the constructor as
basic_string(const value_type* s, const Allocator& a = Allocator());
The implicit deduction guides from class template argument deduction make what was previously an implementation detail visible:
std::basic_string s = "foo"; // error, can't deduce charT.
The constructor in question is in the libc++ DSO, but fortunately it looks like fixing this will not result in an ABI break.
@rsmith How does this look? I did more than just the constructors mentioned in the PR, but IDK how far to take it.
Reviewers: mclow.lists, rsmith
Reviewed By: rsmith
Subscribers: cfe-commits, rsmith
Differential Revision: https://reviews.llvm.org/D29863
llvm-svn: 295393
diff --git a/libcxx/test/support/constexpr_char_traits.hpp b/libcxx/test/support/constexpr_char_traits.hpp
index 2136b26..7508567 100644
--- a/libcxx/test/support/constexpr_char_traits.hpp
+++ b/libcxx/test/support/constexpr_char_traits.hpp
@@ -12,6 +12,7 @@
#define _CONSTEXPR_CHAR_TRAITS
#include <string>
+#include <cassert>
#include "test_macros.h"
@@ -118,7 +119,7 @@
TEST_CONSTEXPR_CXX14 _CharT*
constexpr_char_traits<_CharT>::copy(char_type* __s1, const char_type* __s2, size_t __n)
{
- _LIBCPP_ASSERT(__s2 < __s1 || __s2 >= __s1+__n, "char_traits::copy overlapped range");
+ assert(__s2 < __s1 || __s2 >= __s1+__n);
char_type* __r = __s1;
for (; __n; --__n, ++__s1, ++__s2)
assign(*__s1, *__s2);