[R] problems when compiling C code

[Stephane DRAY]

Hello,

I would like to call C code from R. My C code is divided in two files. In 
the file "testpermut.c", I have the following lines:

#include "adesub.h"

In my working folder, I have the files:
- adesub.c which contains general functions
- adesub.h with the header of functions contained in adesub.c
- testpermut.c which call some functions defined in adesub.c

When I try to  create my dll (Work on Windows XP, R-1.8.1), I obtain error 
message:

$ Rcmd shlib testpermut.c
making adesub.d from adesub.c
making testpermut.d from testpermut.c
gcc   -Ic:/Rdev/R-1.8.1/src/include -Wall -O2   -c testpermut.c -o testpermut.o
ar cr testpermut.a *.o
ranlib testpermut.a
gcc  --shared -s  -o testpermut.dll testpermut.def 
testpermut.a  -Lc:/Rdev/R-1.8
.1/src/gnuwin32  -lg2c -lR
testpermut.a(testpermut.o.b)(.text+0x35):testpermut.c: undefined reference 
to `taballoc'
testpermut.a(testpermut.o.b)(.text+0x49):testpermut.c: undefined reference 
to `taballoc'
testpermut.a(testpermut.o.b)(.text+0x62):testpermut.c: undefined reference 
to `taballoc'
testpermut.a(testpermut.o.b)(.text+0x14c):testpermut.c: undefined reference 
to `freetab'
testpermut.a(testpermut.o.b)(.text+0x156):testpermut.c: undefined reference 
to `freetab'
testpermut.a(testpermut.o.b)(.text+0x160):testpermut.c: undefined reference 
to `freetab'
testpermut.a(testpermut.o.b)(.text+0x192):testpermut.c: undefined reference 
to `taballoc'
testpermut.a(testpermut.o.b)(.text+0x22b):testpermut.c: undefined reference 
to `taballoc'
testpermut.a(testpermut.o.b)(.text+0x23f):testpermut.c: undefined reference 
to `vecalloc'
testpermut.a(testpermut.o.b)(.text+0x24b):testpermut.c: undefined reference 
to `vecalloc'
testpermut.a(testpermut.o.b)(.text+0x339):testpermut.c: undefined reference 
to `freevec'
testpermut.a(testpermut.o.b)(.text+0x343):testpermut.c: undefined reference 
to `freevec'
testpermut.a(testpermut.o.b)(.text+0x34d):testpermut.c: undefined reference 
to `freetab'
testpermut.a(testpermut.o.b)(.text+0x412):testpermut.c: undefined reference 
to `taballoc'
make: *** [testpermut.dll] Error 1
$

The functions taballoc, freetab, vecalloc and freevec are defined in adesub 
files. So it seems that gcc does not make the links between my files. If I 
include the problematic functions in testpermut.c, gcc works perfectly and 
my dll is created.

Perhaps someone could explain me what is my problem although it is not an R 
problem but probably a misuse of gcc ?.

Thanks in advance.
Stéphane DRAY
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Département des Sciences Biologiques
Université de Montréal, C.P. 6128, succursale centre-ville
Montréal, Québec H3C 3J7, Canada

Tel : 514 343 6111 poste 1233
E-mail : stephane.dray at umontreal.ca
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