Compiling (formatting problem?)

[John E]

#define OMWFMT64 L"I64"

void
integerToString(const OMByte* value, wchar_t* str)
{
	// Some stuff

	std_swprintf(str, 21, L"%"OMWFMT64 L"u", *((OMUInt64*)value)); // <--- this line
}

The indicated line compiles fine with VS2005 but it fails to compile with VS2015 Community Edition, giving me these errors:-

error C3688: invalid literal suffix 'OMWFMT64'; literal operator or literal operator template 'operator ""OMWFMT64' not found
error C2664: 'int _snwprintf(wchar_t *,std::size_t,const wchar_t *,...)': cannot convert argument 3 from 'OMUInt64' to 'const wchar_t *'

Does this make sense to anyone? Or have I discovered a bug in VS2015?

It seems to be a problem with the #define because if I change the line to this, it does compile:-

	std_swprintf(str, 21, L"%I64" L"u", *((OMUInt64*)value));

[John E]

Maybe there's a problem with concatenation in VS2015 because inserting a space also fixes the problem. i.e. change from this

#define OMWFMT64 L"I64"

std_swprintf(str, 21, L"%"OMWFMT64 L"u", *((OMUInt64*)value));

to this

#define OMWFMT64 L"I64"

std_swprintf(str, 21, L"%" OMWFMT64 L"u", *((OMUInt64*)value));

[2kaud]

with concatenation in VS2015

Not a problem but a documented breaking change due to the introduction of user-defined literals.

String literals followed by macros

The compiler now supports user defined literals. As a consequence, string literals followed by macros without any intervening whitespace are interpreted as user-defined literals, which might produce errors or unexpected results.

See https://msdn.microsoft.com/en-us/library/bb531344.aspx

[Arjay]

John, you might want to consider updating to the 2017 Community Edition. That way, you can resolve any breaking changes and be up to date with the current compiler.

[John E]

Thanks 2kaud, that makes sense now

Arjay... I'm not nearly adventurous enough to be one of life's 'early adopters'!! I did migrate to VS2015 Community Edition (last year sometime) but I still remember how it would sometimes take 3-4 minutes to appear on screen, after clicking the icon (I assume it must have been updating from the internet maybe). I'm afraid I don't have much patience with stuff like that...

[2kaud]

You can have both VS2015 Community and VS2017 Community installed and both running on the same computer. I have VS2013, VS2015 and VS2017 installed. Also note that from the installed latest version if you previous versions installed you can compile for that version (Properties/General/Platform toolset). ie On my system from VS2017 I can compile for 13, 15 and 17. Try VS2017, you have nothing to loose (just some disk space!).

how it would sometimes take 3-4 minutes to appear on screen

VS2015 start-up is very disk intensive - so if you have a slow disk..... This has been improved with VS2017.

Improved startup and improved project load. Multiple enhancements come together to make Visual Studio 2017 start up faster than Visual Studio 2015. Solution load times are shorter, and build performance is faster, particularly for C++ projects

See https://blogs.msdn.microsoft.com/vis...-and-partners/