Is this C++11 or whatever ?

[John E]

I have a project here which I still need to build with MSVC 8.0 (VS2005). Today, someone upstream added the following code:-

// In a header file:-
    typedef enum _cairo_svg_unit {
        CAIRO_SVG_UNIT_USER = 0,
        CAIRO_SVG_UNIT_EM,
        CAIRO_SVG_UNIT_EX,
        CAIRO_SVG_UNIT_PX,
        CAIRO_SVG_UNIT_IN,
        CAIRO_SVG_UNIT_CM,
        CAIRO_SVG_UNIT_MM,
        CAIRO_SVG_UNIT_PT,
        CAIRO_SVG_UNIT_PC,
        CAIRO_SVG_UNIT_PERCENT
    } cairo_svg_unit_t;


// In a source file:-
    static const char * _cairo_svg_unit_strings[] =
    {
        [CAIRO_SVG_UNIT_USER] = "",  // <--- error occurs here !!
        [CAIRO_SVG_UNIT_EM] = "em",
        [CAIRO_SVG_UNIT_EX] = "ex",
        [CAIRO_SVG_UNIT_PX] = "px",
        [CAIRO_SVG_UNIT_IN] = "in",
        [CAIRO_SVG_UNIT_CM] = "cm",
        [CAIRO_SVG_UNIT_MM] = "mm",
        [CAIRO_SVG_UNIT_PT] = "pt",
        [CAIRO_SVG_UNIT_PC] = "pc",
        [CAIRO_SVG_UNIT_PERCENT] = "%"
    };

MSVC complains giving me error C2059: syntax error : '['

I'm guessing this is some unsupported syntax which got added later than 2005?

[2kaud]

This doesn't compile as c++ in VS2017 either - same issue! It looks like the code is trying to specify the element of the array to be initialised. AFAIK this isn't standard c++ syntax.

To get this to compile, something like

// In a source file:-
	static const char * _cairo_svg_unit_strings[] =
	{
		 "",  // <--- error occurs here !!
		"em",
		"ex",
		"px",
		"in",
		"cm",
		"mm",
		"pt",
		"pc",
		 "%"
	};

[Igor Vartanov]

This is C99 designated initialization. See Initialization from brace-enclosed lists section here.

#include <stdio.h>

const char * s0[] = {
    "s0_0",
    "s0_1",
    NULL,
};

#ifdef C99_INIT
const char * s1[] = {
    [0] = "s1_0",
    [1] = "s1_1",
    [2] = NULL,
};
#endif

int main()
{
    for (const char **s = s0; *s != NULL; s++)
        printf("%s\n", *s);
#ifdef C99_INIT
    for (const char **s = s1; *s != NULL; s++)
        printf("%s\n", *s);
#endif
    return 0;
}

Linux:

$ g++ 142.cpp
$ ./a.out
s0_0
s0_1
$ g++ 142.cpp -DC99_INIT
$ ./a.out
s0_0
s0_1
s1_0
s1_1

Windows, VS2012:

J:\Temp\142>cl 142.cpp
Microsoft (R) C/C++ Optimizing Compiler Version 17.00.50727.1 for x86
Copyright (C) Microsoft Corporation.  All rights reserved.

142.cpp
Microsoft (R) Incremental Linker Version 11.00.50727.1
Copyright (C) Microsoft Corporation.  All rights reserved.

/out:142.exe
142.obj

J:\Temp\142>142
s0_0
s0_1

J:\Temp\142>cl 142.cpp /DC99_INIT
Microsoft (R) C/C++ Optimizing Compiler Version 17.00.50727.1 for x86
Copyright (C) Microsoft Corporation.  All rights reserved.

142.cpp
142.cpp(11) : error C2143: syntax error : missing ']' before 'constant'
142.cpp(11) : error C2059: syntax error : ']'
142.cpp(11) : error C2059: syntax error : 'constant'
142.cpp(14) : error C2143: syntax error : missing ';' before '}'
142.cpp(14) : error C2059: syntax error : '}'

[John E]

Thanks guys...