<format>: error C2668 when import <format> as header unit and use std::format_to #1919
Description
Describe the bug
When import <format> as a headerunit, using std::format_to leads to an error C2668 in Release mode.
This problem does not occur in Debug mode.
Command-line test case
D:\cpptest>type repro.cpp
import <format>;
import <string>;
int main()
{
std::string msg;
std::format_to(std::back_inserter(msg), "{}", "");
return 0;
}
D:\cpptest>cl /std:c++20 /permissive- /GS /GL /W3 /Gy /Zc:wchar_t /Zi /Gm- /O2 /sdl /Zc:inline /fp:precise /D "NDEBUG" /D "_CONSOLE" /D "_UNICODE" /D "UNICODE" /WX- /Zc:forScope /Gd /Oi /MD /std:c++20 /EHsc /nologo /exportHeader /headerName:angle format string
format
string
D:\cpptest>cl /std:c++20 /permissive- /GS /GL /W3 /Gy /Zc:wchar_t /Zi /Gm- /O2 /sdl /Zc:inline /fp:precise /D "NDEBUG" /D "_CONSOLE" /D "_UNICODE" /D "UNICODE" /WX- /Zc:forScope /Gd /Oi /MD /std:c++20 /EHsc /nologo /headerUnit:angle format=format.ifc /headerUnit:angle string=string.ifc repro.cpp /c
repro.cpp
D:\Program Files (x86)\Microsoft Visual Studio\2019\Preview\VC\Tools\MSVC\14.29.30035\include\format(2461): error C2668: 'abs': ambiguous call to overloaded function
D:\Program Files (x86)\Microsoft Visual Studio\2019\Preview\VC\Tools\MSVC\14.29.30035\include\cstdlib(27): note: could be 'float abs(float) noexcept'
D:\Program Files (x86)\Microsoft Visual Studio\2019\Preview\VC\Tools\MSVC\14.29.30035\include\cstdlib(27): note: or 'float abs(float) noexcept'
D:\Program Files (x86)\Microsoft Visual Studio\2019\Preview\VC\Tools\MSVC\14.29.30035\include\format(2461): note: while trying to match the argument list '(const _Float)'
......
Expected behavior
The file should compile successfully.
STL version
Microsoft Visual Studio Enterprise 2019 Preview
Version 16.10.0 Preview 3.0