variations of int sizes (and signded/unsigned) between platorms

[Daniel Keep]

Jason House wrote:
> I have a small section of code that is giving me issues moving between
> two machines.  On my amd64 machine, find returns a long and the slice
> operation expects ulongs.  On my friend's machine, find returns an int
> and refuses to accept cast(ulong)startComment.  Maybe it should be
> cast(uint)startComment?  Of course, that won't work on my machine.
> 
> Rather that try to decipher this with version checks (when I don't know
> how this varies from system to system), what's the proper way to solve
> this?  I'm using gdc on my amd64 machine.  I'm not sure if my friend is
> using gdc or dmd... or even if this is a variation form one version of
> phobos to another.
> 
>> $ dsss build
>> housebot.d => housebot-0.6
>> + /bin/rebuild -Idsss_imports/ -I. -S./ -I/include/d -S/lib/  
>> -oqdsss_objs -Dddoc -unittest -w -g housebot.d -ofhousebot-0.6
>> warning - gtp.d:105: Error: implicit conversion of expression
>> (startComment) of type long to ulong can cause loss of data
>> Command /bin/rebuild returned with code 256, aborting.
>>
>> $ head -n 108 gtp.d | tail
>>
>>         private void getArgs(out char[][] args){
>>                 char[] line = inStream.readLine();
>>                 auto startComment = find(line, "#");
>>                 char[] commentFree = line;
>>                 if (startComment > -1)
>>                         commentFree = line[0..startComment];
>>                 // Remove starting whitespace, trailing whitespace
>>                 // Also replace sequences of spaces and tabs with a
>> single space
>>                 char[] squeezedLine = strip(squeeze(tr(line, "\t","
>> ")," "));

find should probably be returning ptrdiff_t, since that looks like what
you're getting.  If you try casting startComment to size_t on line 105,
that should work.

FYI:
          | 32-bit alias | 64-bit alias |
size_t    |     uint     |     ulong    |
ptrdiff_t |     int      |     long     |

Hope that helps.

	-- Daniel

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