VS2015 warnings

[jry2]

I'm getting following warnings when compiling Nano SVG with VS 2015 RC. I will prepare PR with fixes, unfortunately I'm not able to test Xcode, only VC2015 and GCC. Note: I used premake5.exe vs2015 to make projects, it works fine.

1>------ Rebuild All started: Project: example2, Configuration: Debug Win32 ------
1>  example2.c
1>e:\source\nanosvg\example\stb_image_write.h(156): warning C4996: 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
1>  c:\program files (x86)\windows kits\10\include\10.0.10056.0\ucrt\stdio.h(205): note: see declaration of 'fopen'
1>e:\source\nanosvg\example\stb_image_write.h(348): warning C4456: declaration of 'i' hides previous local declaration
1>  e:\source\nanosvg\example\stb_image_write.h(271): note: see declaration of 'i'
1>e:\source\nanosvg\example\stb_image_write.h(349): warning C4456: declaration of 'j' hides previous local declaration
1>  e:\source\nanosvg\example\stb_image_write.h(271): note: see declaration of 'j'
1>e:\source\nanosvg\example\stb_image_write.h(495): warning C4996: 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
1>  c:\program files (x86)\windows kits\10\include\10.0.10056.0\ucrt\stdio.h(205): note: see declaration of 'fopen'
1>e:\source\nanosvg\src\nanosvg.h(120): warning C4201: nonstandard extension used: nameless struct/union
1>e:\source\nanosvg\src\nanosvg.h(359): warning C4201: nonstandard extension used: nameless struct/union
1>e:\source\nanosvg\src\nanosvg.h(730): warning C4127: conditional expression is constant
1>e:\source\nanosvg\src\nanosvg.h(2487): warning C4127: conditional expression is constant
1>e:\source\nanosvg\src\nanosvg.h(2488): warning C4127: conditional expression is constant
1>e:\source\nanosvg\src\nanosvgrast.h(251): warning C4244: '=': conversion from 'int' to 'unsigned char', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(632): warning C4456: declaration of 's' hides previous local declaration
1>  e:\source\nanosvg\src\nanosvgrast.h(577): note: see declaration of 's'
1>e:\source\nanosvg\src\nanosvgrast.h(753): warning C4244: '=': conversion from 'float' to 'int', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(755): warning C4244: '=': conversion from 'float' to 'int', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(756): warning C4244: '=': conversion from 'float' to 'int', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(849): warning C4244: 'function': conversion from 'int' to 'unsigned char', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(844): warning C4244: 'initializing': conversion from 'float' to 'int', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(859): warning C4244: 'function': conversion from 'int' to 'unsigned char', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(854): warning C4244: 'initializing': conversion from 'float' to 'int', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(1093): warning C4244: '=': conversion from 'int' to 'unsigned char', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(1094): warning C4244: '=': conversion from 'int' to 'unsigned char', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(1095): warning C4244: '=': conversion from 'int' to 'unsigned char', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(1132): warning C4244: '=': conversion from 'int' to 'unsigned char', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(1133): warning C4244: '=': conversion from 'int' to 'unsigned char', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(1134): warning C4244: '=': conversion from 'int' to 'unsigned char', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(1174): warning C4244: '=': conversion from 'float' to 'int', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(1175): warning C4244: '=': conversion from 'float' to 'int', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(1185): warning C4244: '=': conversion from 'float' to 'int', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(1186): warning C4244: '=': conversion from 'float' to 'int', possible loss of data
1>e:\source\nanosvg\example\example2.c(43): warning C4244: '=': conversion from 'float' to 'int', possible loss of data
1>e:\source\nanosvg\example\example2.c(44): warning C4244: '=': conversion from 'float' to 'int', possible loss of data
1>e:\source\nanosvg\src\nanosvgrast.h(1198): warning C4701: potentially uninitialized local variable 'cb' used
1>e:\source\nanosvg\src\nanosvgrast.h(708): warning C4701: potentially uninitialized local variable 'right' used
1>e:\source\nanosvg\src\nanosvgrast.h(707): warning C4701: potentially uninitialized local variable 'left' used
1>e:\source\nanosvg\src\nanosvgrast.h(707): warning C4701: potentially uninitialized local variable 'firstLeft' used
1>e:\source\nanosvg\src\nanosvgrast.h(708): warning C4701: potentially uninitialized local variable 'firstRight' used
1>e:\source\nanosvg\src\nanosvgrast.h(435): warning C4701: potentially uninitialized local variable 'prevy' used
1>e:\source\nanosvg\src\nanosvgrast.h(435): warning C4701: potentially uninitialized local variable 'prevx' used
1>e:\source\nanosvg\src\nanosvgrast.h(448): warning C4701: potentially uninitialized local variable 'lx' used
1>e:\source\nanosvg\src\nanosvgrast.h(448): warning C4701: potentially uninitialized local variable 'ly' used
1>e:\source\nanosvg\src\nanosvgrast.h(449): warning C4701: potentially uninitialized local variable 'rx' used
1>e:\source\nanosvg\src\nanosvgrast.h(449): warning C4701: potentially uninitialized local variable 'ry' used
1>  example2.vcxproj -> E:\Source\nanosvg\build\.\example2.exe
========== Rebuild All: 1 succeeded, 0 failed, 0 skipped ==========

[memononen]

The warnings about nanosvg/rast.h looks sane things to fix.

I really really really hate the warnings about NSVG_NOTUSED. A new compiler, and we're back to square one again, and again.

If upstream stb_image_write fixes the warnings, let's update, else just leave it as is.

Thanks for taking the time to improve the code!

[jry2]

Could you please check this version in Xcode? It compiles without warnigs with GCC 4.7.2 and VC2015 RC.

#define NSVG_NOTUSED(v) ((void)(v))

[jry2]

Upstream stb_image_write.h is even worse than your version ;-) I will patch only nanosvg.h and nanosvgrast.h warnings.

1>e:\source\nanosvg\example\stb_image_write.h(210): warning C4996: 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
1>  c:\program files (x86)\windows kits\10\include\10.0.10056.0\ucrt\stdio.h(205): note: see declaration of 'fopen'
1>e:\source\nanosvg\example\stb_image_write.h(329): warning C4457: declaration of 'comp' hides function parameter
1>  e:\source\nanosvg\example\stb_image_write.h(278): note: see declaration of 'comp'
1>e:\source\nanosvg\example\stb_image_write.h(372): warning C4996: 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
1>  c:\program files (x86)\windows kits\10\include\10.0.10056.0\ucrt\stdio.h(205): note: see declaration of 'fopen'
1>e:\source\nanosvg\example\stb_image_write.h(553): warning C4456: declaration of 'i' hides previous local declaration
1>  e:\source\nanosvg\example\stb_image_write.h(476): note: see declaration of 'i'
1>e:\source\nanosvg\example\stb_image_write.h(554): warning C4456: declaration of 'j' hides previous local declaration
1>  e:\source\nanosvg\example\stb_image_write.h(476): note: see declaration of 'j'
1>e:\source\nanosvg\example\stb_image_write.h(702): warning C4996: 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.

[memononen]

I have used that unused macro before, and cannot remember anymore why I changed that. It might have been gcc with tighter warning level.

[jry2]

Some warnings are fixed in #42
I didn't fix following warnings:

1>E:\Source\nanosvg\src\nanosvg.h(120): warning C4201: nonstandard extension used: nameless struct/union
1>E:\Source\nanosvg\src\nanosvg.h(359): warning C4201: nonstandard extension used: nameless struct/union
1>E:\Source\nanosvg\src\nanosvg.h(730): warning C4127: conditional expression is constant
1>E:\Source\nanosvg\src\nanosvg.h(2487): warning C4127: conditional expression is constant
1>E:\Source\nanosvg\src\nanosvg.h(2488): warning C4127: conditional expression is constant

C4201 nonstandard extension used should be probably fixed in VC project, because anonymous structures and unions are valid in C11.
C4127 conditional expression is constant is problematic NSVG_NOTUSED macro.