Module symbol name link problem

[tried100times]

Hi,

I am new to linking issues on Windows so I suspect my problem is a simple one. I am trying to build a Matlab mex function.

My mexFunction is just a wrapper which calls another function from a small module (finfo). Compilation of both module and mexfunction go fine, but I get an unresolved external symbol error at link:

[bash]>> mex -c finfo.f90
>> mex -v -ID:\code\MatlabAPI.git calc_info.f d:\code\rahim\finfo.obj d:\code\MatlabAPI.git\MatlabAPImx.obj d:\code\MatlabAPI.git\MatlabAPImex.obj C:\AMD\acml4.4.0\ifort64\lib\libacml_mv.lib
-> Default options filename found in C:\Users\rince\AppData\Roaming\MathWorks\MATLAB\R2010b 
---------------------------------------------------------------- 
->    Options file           = C:\Users\rince\AppData\Roaming\MathWorks\MATLAB\R2010b\mexopts.bat 
      MATLAB                 = C:\Program Files\MATLAB\R2010b 
->    COMPILER               = ifort 
->    Compiler flags: 
         COMPFLAGS           = /fpp /free /Qprec "/IC:\Program Files\MATLAB\R2010b/extern/include" -c -nologo -DMATLAB_MEX_FILE /MD /fp:source /assume:bscc /Qopenmp 
         OPTIMFLAGS          = /O2 /DNDEBUG 
         DEBUGFLAGS          = /Z7 
         arguments           =  -ID:\code\MatlabAPI.git 
         Name switch         = /Fo 
->    Pre-linking commands   =  
->    LINKER                 = link 
->    Link directives: 
         LINKFLAGS           = /dll /export:MEXFUNCTION /LIBPATH:"C:\Program Files\MATLAB\R2010b\extern\lib\win64\microsoft" libmx.lib libmex.lib libmat.lib /implib:"C:\Users\rince\AppData\Local\Temp\mex_JSZ0fe\templib.x" /MAP:"calc_info.mexw64.map" /NOLOGO /INCREMENTAL:NO 
         LINKDEBUGFLAGS      = /debug /PDB:"calc_info.mexw64.pdb" 
         LINKFLAGSPOST       =  
         Name directive      = /out:"calc_info.mexw64" 
         File link directive =  
         Lib. link directive =  
         Rsp file indicator  = @ 
->    Resource Compiler      = rc /fo "mexversion.res" 
->    Resource Linker        =  
---------------------------------------------------------------- 
 
 
--> ifort  -ID:\code\MatlabAPI.git /fpp /free /Qprec "/IC:\Program Files\MATLAB\R2010b/extern/include" -c -nologo -DMATLAB_MEX_FILE /MD /fp:source /assume:bscc /Qopenmp /FoC:\Users\rince\AppData\Local\Temp\mex_JSZ0fe\calc_info.obj /O2 /DNDEBUG -DMX_COMPAT_32 calc_info.f 
 
    Contents of C:\Users\rince\AppData\Local\Temp\mex_JSZ0fe\mex_tmp.rsp: 
  C:\Users\rince\AppData\Local\Temp\mex_JSZ0fe\calc_info.obj  D:\code\rahim\finfo.obj  D:\code\MatlabAPI.git\MatlabAPImx.obj  D:\code\MatlabAPI.git\MatlabAPImex.obj  C:\AMD\acml4.4.0\ifort64\lib\libacml_mv.lib 
 
 
--> link /out:"calc_info.mexw64" /dll /export:MEXFUNCTION /LIBPATH:"C:\Program Files\MATLAB\R2010b\extern\lib\win64\microsoft" libmx.lib libmex.lib libmat.lib /implib:"C:\Users\rince\AppData\Local\Temp\mex_JSZ0fe\templib.x" /MAP:"calc_info.mexw64.map" /NOLOGO /INCREMENTAL:NO  @C:\Users\rince\AppData\Local\Temp\mex_JSZ0fe\mex_tmp.rsp   
 
   Creating library C:\Users\rince\AppData\Local\Temp\mex_JSZ0fe\templib.x and object C:\Users\rince\AppData\Local\Temp\mex_JSZ0fe\templib.exp 
calc_info.obj : error LNK2019: unresolved external symbol CALC_INFO referenced in function MEXFUNCTION 
calc_info.mexw64 : fatal error LNK1120: 1 unresolved externals 
 
  C:\PROGRA~1\MATLAB\R2010B\BIN\MEX.PL: Error: Link of 'calc_info.mexw64' failed. 
 [/bash]

When I look at the symbol names with dumpbin,

In the mexFunction calc_info.obj:
012 00000000 UNDEF notype () External | CALC_INFO

In the finfo module object finfo.obj:
00B 000016C0 SECT2 notype () External | FINFO_mp_CALCINFO

So I don't understand why it is External in the compiled module? And how to resolve my undefined symbol.

Thanks

[mecej4]

Subprogram names declared inside CONTAINS .. END .. appear decorated with the module name in the object files.

Either use the decorated name in calc_info.f90, or place the subprogram calc_info outside any modules.

Make sure that the name is used consistently; CALC_INFO and CALCINFO do not match.

[tried100times]

Thanks very much for help! It was an inconsistency with the underscore and so completely my fault! I didn't spot it becuase I assumed the underscore was removed as part of the name mangling.

Thanks again.

[mecej4]

>I assumed the underscore was removed as part of the name mangling

On the contrary, the underscore is used in symbol names precisely because humans tend to ignore it and computers do not!