C2220: the following warning is treated as an error

[bipul-mohanto]

Hi! I am using Visual Studio 2022 (x64: windows), to build Falcor SDK, that as fmt library as external.

While I am building the SDK as Debug, it is returning the above error: C2220: the following warning is treated as an error. The error shows to format.h line 559: template using checked_ptr = stdext::checked_array_iterator<T*>

The release build is working fine. I tried to lower the vS warning level to W3, disable Treat Warnings As Errors, also tried with the latest clone replacing the existing library. but it is no use. Any suggestion?

[vitaut]

checked_array_iterator was removed back in 2023 (see #3540) so you might need to update to a more recent version to {fmt}.

[bipul-mohanto]

So, are you suggesting replacing my existing fmt with the latest one? I have tried with the Release 11.0.2, however, getting errors in both release and debug build as:
Is any specific version compatible with Falcor? Falcor has the default fmt version: 10.0.0 - 2023-05-09

7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         with
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         [
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             Context=fmt::v11::format_context,
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             FormatContext=fmt::v11::format_context
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         ]
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         and
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         [
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             Formatter=fmt::v11::formatter<std::filesystem::path,char,void>
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         ]
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662: 'fmt::v11::appender fmt::v11::formatter<std::filesystem::path,char,void>::format<Context>(const std::filesystem::path &,FormatContext &)': cannot convert 'this' pointer from 'const Formatter' to 'fmt::v11::formatter<std::filesystem::path,char,void> &'
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         with
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         [
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             Context=fmt::v11::format_context,
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             FormatContext=fmt::v11::format_context
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         ]
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         and
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         [
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             Formatter=fmt::v11::formatter<std::filesystem::path,char,void>
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         ]
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662: 'fmt::v11::appender fmt::v11::formatter<std::filesystem::path,char,void>::format<Context>(const std::filesystem::path &,FormatContext &)': cannot convert 'this' pointer from 'const Formatter' to 'fmt::v11::formatter<std::filesystem::path,char,void> &'
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         with
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         [
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             Context=fmt::v11::format_context,
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             FormatContext=fmt::v11::format_context
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         ]
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         and
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         [
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             Formatter=fmt::v11::formatter<std::filesystem::path,char,void>
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         ]
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662: 'fmt::v11::appender fmt::v11::formatter<std::filesystem::path,char,void>::format<Context>(const std::filesystem::path &,FormatContext &)': cannot convert 'this' pointer from 'const Formatter' to 'fmt::v11::formatter<std::filesystem::path,char,void> &'
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         with
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         [
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             Context=fmt::v11::format_context,
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             FormatContext=fmt::v11::format_context
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         ]
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         and
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         [
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             Formatter=fmt::v11::formatter<std::filesystem::path,char,void>
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         ]
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662: 'fmt::v11::appender fmt::v11::formatter<std::filesystem::path,char,void>::format<Context>(const std::filesystem::path &,FormatContext &)': cannot convert 'this' pointer from 'const Formatter' to 'fmt::v11::formatter<std::filesystem::path,char,void> &'
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         with
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         [
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             Context=fmt::v11::format_context,
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             FormatContext=fmt::v11::format_context
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         ]
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         and
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         [
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:             Formatter=fmt::v11::formatter<std::filesystem::path,char,void>
7>C:\Users\local-admin\Desktop\Falcor\external\fmt\include\fmt\base.h(1402,23): error C2662:         ]

[bipul-mohanto]

I got a temporary solution; mention it here as a future reference.

Replace #if defined(_SECURE_SCL) && _SECURE_SCL with #if 0

// Make a checked iterator to avoid MSVC warnings.
template <typename T> using checked_ptr = stdext::checked_array_iterator<T*>;

[mwinterb]

Falcor defines its own formatters for std types instead of using the definitions in fmt/std.h. Which is explicitly bad because of ODR violations. And for v11, they're bad because the format function isn't const. (Even before v11 they were required to be const if formatting ranges.) Some of their formatters for their own types do have format as const, but it isn't consistent.
https://github.com/NVIDIAGameWorks/Falcor/blob/master/Source/Falcor/Utils/StringFormatters.h#L35

[vitaut]

I recommend reporting an issue to Falcor.