I had the same problem and I solved it as follows.
My computer is
MAC Os X Snow Leopard 10.6.7
Macbook
Grass GIS 6.4.1
COPY FROM TERMINAL
$ sudo cp -r /Applications/GRASS-6.4.app/Contents/MacOS/include/grass/ /Users/Shared/src/GRASS/grass-6.4.1-snow/dist.i386-apple-darwin10.7.0/include/grass # For error gis.h
$ sudo cp -r /Library/GRASS/6.4/modbuild/tools/ /Users/Shared/src/GRASS/grass-6.4.1-snow/tools # for error g.html2man
$ sudo mkdir /Applications/GRASS-6.4.app/Contents/MacOS/tools
$ sudo cp /Library/GRASS/6.4/modbuild/tools/mkhtml.sh /Applications/GRASS-6.4.app/Contents/MacOS/tools # for error mkhtml.sh
AFTER AGAIN TO INSTALL TO EXTENSION, OK
g.extension ETC ETC.
Tell me your result, ok
On May 4, 2011, at 1:11 PM, Jason Lessels wrote:
><i> Hi,
</i>><i> I am running os x snow leopard (10.6.7). I have tried to install an extension in GRASS 6.4.1 (2011), but it throws a compilation error. I have searched the lists, with no luck, could anyone help me with this problem.
</i>><i> Thanks
</i>><i> Jason
</i>> ><i> g.extension extension=i.landsat.toar
</i>><i> Fetching <i.landsat.toar> from GRASS-Addons SVN (be patient)...
</i>><i> A i.landsat.toar/landsat_set.c
</i>><i> A i.landsat.toar/local_proto.h
</i>><i> A i.landsat.toar/main.c
</i>><i> A i.landsat.toar/description.html
</i>><i> A i.landsat.toar/landsat.c
</i>><i> A i.landsat.toar/earth_sun.c
</i>><i> A i.landsat.toar/landsat.h
</i>><i> A i.landsat.toar/landsat_met.c
</i>><i> A i.landsat.toar/Makefile
</i>><i> A i.landsat.toar/earth_sun.h
</i>><i> U i.landsat.toar
</i>><i> Checked out revision 46186.
</i>><i> Compiling <i.landsat.toar>...
</i>><i> test -d OBJ.i386-apple-darwin10.7.0 || mkdir -p OBJ.i386-apple-darwin10.7.0
</i>><i> gcc -I/Users/Shared/src/GRASS/grass-6.4.1-snow/dist.i386-apple-darwin10.7.0/include -Os -fexceptions -arch i386 -arch x86_64 -DPACKAGE=\""grassmods"\" -I/Users/Shared/src/GRASS/grass-6.4.1-snow/dist.i386-apple-darwin10.7.0/include -o OBJ.i386-apple-darwin10.7.0/earth_sun.o -c earth_sun.c
</i>><i> gcc -I/Users/Shared/src/GRASS/grass-6.4.1-snow/dist.i386-apple-darwin10.7.0/include -Os -fexceptions -arch i386 -arch x86_64 -DPACKAGE=\""grassmods"\" -I/Users/Shared/src/GRASS/grass-6.4.1-snow/dist.i386-apple-darwin10.7.0/include -o OBJ.i386-apple-darwin10.7.0/landsat.o -c landsat.c
</i>><i> landsat.c:4:23: error: grass/gis.h: No such file or directory
</i>><i> landsat.c:4:23: error: grass/gis.h: No such file or directory
</i>><i> lipo: can't figure out the architecture type of: /Users/jasonlessels/git/muttama/gis/muttama/muttama/.tmp/macintosh-3.localdomain/29713.0/ccdiXykN.out
</i>><i> make: *** [OBJ.i386-apple-darwin10.7.0/landsat.o] Error 1
</i>><i> ERROR: Compilation failed, sorry. Please check above error messages._______________________________________________
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