Re: Warning when compiling GNUstep

[Richard Frith-Macdonald]

On Monday, July 28, 2003, at 04:52 PM, Yen-Ju Chen wrote:

> These are the warnings I received when compiling GNUstep.
> GNUstep still works, but compilation will looks more clean if they are  
> fixed.
> I use FreeBSD 4.8, GCC 3.2 with lastest GNUstep CVS (7/28 morning).

Almost entirely these warnings are the compiler being stupid ...
Often they don't appear when built with 'debug=yes' since the compiler
then maintains more information about what it is doing, and can tell  
that
some of these things are ok.

> gnustep-base:
>
> GSMime.m: In function `-[GSMimeParser  
> decodeData:fromRange:intoData:withContext:]':
> GSMime.m:780: warning: `src' might be used uninitialized in this  
> function
> GSMime.m: In function `-[GSMimeDocument rawMimeData:]':
> GSMime.m:3853: warning: `boundary' might be used uninitialized in this  
> function
> Unicode.m: In function `GSEncodingFromLocale':
> Unicode.m:450: warning: `encoding' might be used uninitialized in this  
> function
> Unicode.m: In function `GSToUnicode':
> Unicode.m:1288: warning: passing arg 2 of `iconv' from incompatible  
> pointer type
> Unicode.m: In function `GSFromUnicode':
> Unicode.m:1882: warning: passing arg 2 of `iconv' from incompatible  
> pointer type
> NSCalendarDate.m: In function `-[NSCalendarDate(OPENSTEP)  
> years:months:days:hours:minutes:seconds:sinceDate:]':
> NSCalendarDate.m:2169: warning: `tmp' might be used uninitialized in  
> this function
> NSRunLoop.m: In function `-[NSRunLoop(GNUstepExtensions)  
> addEvent:type:watcher:forMode:]':
> NSRunLoop.m:1532: warning: comparison of distinct pointer types lacks  
> a cast
> NSURL.m: In function `unescape':
> NSURL.m:406: warning: `c' might be used uninitialized in this function
> externs.m: In function `GSBuildStrings':
> externs.m:211: warning: multiple declarations for method `initialize'
> /usr/local/lib/gcc-lib/i386-portbld-freebsd4.8/3.2.2/include/objc/ 
> Object.h:43: warning: using `+initialize'
> ../Headers/Foundation/NSObject.h:167: warning: also found  
> `+(void)initialize'
> Compiling file objc-load.m ...
> dynamic-load.h:54: warning: `__objc_dynamic_find_symbol' defined but  
> not used

Most of these, I added tweaks to avoid the warnings, where I could do  
so without
making the code less efficient.

> AGSHtml.m: In function `-[AGSHtml outputNode:to:]':
> AGSHtml.m:1581: warning: unused variable `tmp'

Some unimplemented functionality ... so the warning is probably a good  
reminder.

> gdnc.m: In function `-[GDNCServer registerClient:]':
> gdnc.m:568: warning: method `isProxy' not implemented by protocol
> gdnc.m:572: warning: method `setProtocolForProxy:' not implemented by  
> protocol

Compiler bug ... The code already uses explicit casts to tell the  
compiler what it's doing ...
Upgrading to a more recent compiler should fix that.

> plmerge.m: In function `main':
> plmerge.m:39: warning: `plist' might be used uninitialized in this  
> function
>
> gnustep-gui:
>
> NSOpenGLContext.m: In function `+[NSOpenGLContext currentContext]':
> NSOpenGLContext.m:68: warning: multiple declarations for method  
> `currentContext'
> ../Headers/AppKit/NSOpenGL.h:95: warning: using `+(NSOpenGLContext  
> *)currentContext'
> ../Headers/AppKit/NSGraphicsContext.h:168: warning: also found  
> `+(NSGraphicsContext *)currentContext'
> NSScroller.m: In function `-[NSScroller trackKnob:]':
> NSScroller.m:598: warning: `presentEvent' might be used uninitialized  
> in this function
> NSSound.m:86: warning: `the_server' defined but not used
> NSTextView.m:2258: warning: incomplete implementation of class  
> `NSTextView'
> NSTextView.m:2258: warning: method definition for `-selectedRange' not  
> found
> NSTextView.m:2258: warning: class `NSTextView' does not fully  
> implement the `NSTextInput' protocol
> GSHorizontalTypesetter.m: In function `-[GSHorizontalTypesetter  
> layoutGlyphsInLayoutManager:inTextContainer:startingAtGlyphIndex:previo 
> usLineFragmentRect:nextGlyphIndex:numberOfLineFragments:]':
> GSHorizontalTypesetter.m:1100: warning: `ret' might be used  
> uninitialized in this function
> NSPasteboard.m: In function `-[GSFiltered  
> pasteboard:provideDataForType:]':
> NSPasteboard.m:663: warning: `info' might be used uninitialized in  
> this function
> NSPasteboard.m:803: warning: `d' might be used uninitialized in this  
> function
> NSPasteboard.m: In function `+[NSPasteboard pasteboardWithName:]':
> NSPasteboard.m:1188: warning: method `isProxy' not implemented by  
> protocol
> NSPasteboard.m:1192: warning: method `setProtocolForProxy:' not  
> implemented by protocol
> NSPasteboard.m: In function `+[NSPasteboard(Private) _pbs]':
> NSPasteboard.m:1944: warning: method `retain' not implemented by  
> protocol
> NSPasteboard.m:1946: warning: method `connectionForProxy' not  
> implemented by protocol
> NSPasteboard.m:1949: warning: method `setProtocolForProxy:' not  
> implemented by protocol
> NSPasteboard.m: In function `+[NSPasteboard(Private)  
> _pasteboardWithTarget:name:]':
> NSPasteboard.m:2030: warning: comparison of distinct pointer types  
> lacks a cast
> NSPasteboard.m:2033: warning: method `retain' not implemented by  
> protocol
> NSPasteboard.m:2045: warning: method `retain' not implemented by  
> protocol

I think most of the above are due to the compiler bug handling casts  
and protocols ...
upgrading the compiler should fix.

> gnustep-back (with backart):
>
> XGServerEvent.m: In function `-[XGServer(X11Methods)  
> receivedEvent:type:extra:forMode:]':
> XGServerEvent.m:1265: warning: `NSGraphicsContext' does not respond to  
> `gotShmCompletion:'
> XGDragView.m: In function `-[XGDragView _setCursor]':
> XGDragView.m:456: warning: `iname' might be used uninitialized in this  
> function
> blit.m:1348:2: warning: #warning RGB
> blit.m:1374:2: warning: #warning BGR
> blit.m:1400:2: warning: #warning RGBA
> blit.m:1434:2: warning: #warning BGRA
> blit.m:1468:2: warning: #warning ARGB
> blit.m:1502:2: warning: #warning ABGR
> blit.m:1536:2: warning: #warning B5G6R5
> blit.m:1574:2: warning: #warning B5G5R5A1
> Linking tool gpbs ...
> /usr/lib/libc.so.4: WARNING!  setkey(3) not present in the system!
> /usr/lib/libc.so.4: warning: this program uses gets(), which is unsafe.
> /usr/lib/libc.so.4: warning: mktemp() possibly used unsafely; consider  
> using mkstemp()
> /usr/lib/libc.so.4: WARNING!  des_setkey(3) not present in the system!
> /usr/lib/libc.so.4: WARNING!  encrypt(3) not present in the system!
> /usr/lib/libc.so.4: warning: tmpnam() possibly used unsafely; consider  
> using mkstemp()
> /usr/lib/libc.so.4: warning: this program uses f_prealloc(), which is  
> not recommended.
> /usr/lib/libc.so.4: WARNING!  des_cipher(3) not present in the system!
> /usr/lib/libc.so.4: warning: tempnam() possibly used unsafely;  
> consider using mkstemp()

I think that the link warnings are outside our control ... as far as I  
know we don't use any
of the functions mentioned ... so I suspect they are being used by  
other libraries ...
certainly, the only place I could find mktemp() in our source code is  
in NSData.m .... and
it's only used there on operating systems where mkstemp() is not  
available!

So ...
1. I've altered code to avoid warnings (though that doesn't make it any  
more correct)
where it was fairly easy to do so

2. The protocol warnings are a bug in the compiler, and are fixed in  
some later
coimpiler version.

3. link bugs I didn't find in the gnustep code (and don't occur on my  
debian system) ...
perhaps you could find out which librariees the functions are  
referenced in, and
notify the maintainers of those libraries?