Re: [ft-devel] Strict compiler warns at gxvmort2.c

[suzuki toshiya]

Dear Antoine,

Thank you for finding the issue, I think the issue may cause the errors
reported by Sean McBride with clang. I have to fix the signedness issue.

Regards,
mpsuzuki

Antoine Leca wrote:
> Hi Toshiya-san,
> 
> Microsoft's compiler bails out while compiling src/gxvalid/gxvalid.c
> cl /Za /D_CRT_SECURE_NO_DEPRECATE  /Iobjs /I..\freetype2\builds\win32
> /I..\freetype2\include /nologo /c /Ox /W3 /WX /DFT2_BUILD_LIBRARY
> /DFT_CONFIG_MODULES_H="<ftmodule.h>"  /I..\freetype2\src\gxvalid
> /Foobjs\gxvalid.obj ..\freetype2\src\gxvalid\gxvalid.c
> gxvalid.c
> C:\Users\FT\freetype2\src\gxvalid\gxvmort2.c(195) : error C2220: warning
> treated as error - no object file generated
> C:\Users\FT\freetype2\src\gxvalid\gxvmort2.c(195) : warning C4018: '>' :
> signed/unsigned mismatch
> mingw32-make.exe: *** [objs/gxvalid.obj] Error 2
> 
> A quick look shows this is caused by the combination of
>   typedef struct  GXV_mort_subtable_type2_StateOptRec_
>   { /* ... */
>     FT_UShort  ligatureTable;
>     FT_UShort  ligActionTable_length;
> 
> and the actual code
>       FT_ULong   offset;
>     /* ... */
>       } else if ( offset * 2 >
>                   optdata->ligatureTable + optdata->ligatureTable_length )
> 
> The warning is pretty strict but highlights a potential problem on a
> 16-bit target (the sum can overflow, so being a very big negative, which
> will trigger the test in a wrong way.)
> 
> I added a cast (to FT_ULong) to avoid the problem.
> 
> While I was here, I fixed a number of issues with the printf
> specifications in the same area of code; I am not sure this is really
> needed since I guess there are a lot of similar mismatches through the
> codebase (any comments this about?)
> 
> 
> Antoine
>