[csw-maintainers] need help with C++ linker error from Sun's linker

[John Ellson]

James,

Thanks.  I think I understand the issue, but I'm still not sure how to 
fix it?

I'm not that familiar with C++, but I don't see any mismatched 
definitions in the code.

Are you recommending that all "const char* const ... " in the sources be 
changed to
"const char* ... "  ? 

I'm a bit reluctant to make such an extensive change to the API of this 
library.
Is there a linker flag that would tell it to tolerate these extra const's ?

John



James Lee wrote:
> On 27/05/09, 19:25:50, John Ellson <ellson at opencsw.org> wrote regarding
> [csw-maintainers] need help with C++ linker error from Sun's linker:
>
>   
>> If I compile liblasi (mgar/pkg/liblasi/trunk) using g++ it compiles and
>> links without problem.
>>     
>
>   
>> If I use Sun's tools  (remove the line: "CXX=/opt/csw/gcc4/bin/g++ \"
>> from the Makefile)
>> then I get this error:
>>     
>
> ...
>
>   
>> Undefined                       first referenced
>>  symbol                             in file
>> void LASi::PostscriptDocument::setFont(const
>>
>>     
> char*const,LASi::FontStyle,LASi::FontWeight,LASi::FontVariant,LASi::Font
> St
> retch)
>   
>> CMakeFiles/example0.dir/MissingGlyphExample.o
>> ld: fatal: Symbol referencing errors. No output written to example0
>>     
>
>
>
>   
>> There's something odd about the "const char*const"   but I don't know if
>> thats related.
>>     
>
>
> I think you've almost answered your own question.   gcc does not use
> "const" type qualifier for types passed by value when making external
> names.  So "const char*const" is the same as "const char*" on the call
> because the value is copied anyway (the second "const" is of benefit to
> the compiler in the function only).  Nevertheless CC likes consistency
> so try matching the "const"s in all function declarations.
>
>
>
>
> $ cat sub.cc
> void sub(const char*const arg)
> {
>     return;
> }
>
> $ g++ -c sub.cc
> $ nm -C sub.o
>
>
> sub.o:
>
> [Index]   Value      Size    Type  Bind  Other Shndx   Name
>
> [2]     |         0|       0|SECT |LOCL |0    |1      |
> [3]     |         0|       0|SECT |LOCL |0    |2      |
> [4]     |         0|       0|SECT |LOCL |0    |3      |
> [5]     |         0|       0|SECT |LOCL |0    |4      |
> [6]     |         0|      16|FUNC |GLOB |0    |1      |sub(const char*)
>                                                        [_Z3subPKc]
> [1]     |         0|       0|FILE |LOCL |0    |ABS    |sub.cc
>
> $ CC -c sub.cc
> $ nm -C sub.o
>
>
> sub.o:
>
> [Index]   Value      Size    Type  Bind  Other Shndx   Name
>
> [1]     |         0|       0|FILE |LOCL |0    |ABS    |sub.cc
> [2]     |        16|      24|FUNC |GLOB |0    |2      |void sub(const
> char*const)
>
> [__1cDsub6Fkpkc_v_]
>
>
>
>
> James.
> _______________________________________________
> maintainers mailing list
> maintainers at lists.opencsw.org
> https://lists.opencsw.org/mailman/listinfo/maintainers
>
>