Forcing the instantiation of templates in a shared object

[James Kanze]

G++ 3.4.0 under Linux, for what it's worth.

I've got what should be a simple problem: I have a couple of
sources which basically do nothing but instantiate a template,
then declare a local variable of the instantiated type.
Regretfully, when I try to load the .so, I get the following
error:

    Error in dlopen: ./objects/libUTF32LEInputTranslator.so: undefined 
symbol: ConcreteInputTranslator<(anonymous 
namespace)::UTF32LECharacterReader>::read(char*, char*, BasicInput&) const

For some reason, the template is not getting instantiated.

I've tried adding:

    template class ConcreteInputTranslator<UTF32LEInputTranslator> ;

and:
    template class 
ConcreteInputTranslator<UTF32LEInputTranslator>::read(char*, char*, 
BasicInput& ) const;

I've also tried adding a dummy function which called read on the
local object. All to no avail.

The command line I'm using to create the shared library is:

    g++ -o objects/libUTF16BEInputTranslator.so  -shared 
objects/UTF16BEInputTranslator.o -rdynamic

The link of the main is:

    g++ -o objects/test -ansi -ffor-scope -fno-gnu-keywords 
-foperator-names -pipe -Wall -W -Wno-sign-compare -Wno-deprecated 
-Wno-non-virtual-dtor -Wpointer-arith -Wno-unused -D_XOPEN_SOURCE 
-D_XOPENSOURCE_EXTENDED  -ggdb3 -fPIC -DSYSTEM=Unix -I. -I../include 
-I../sources 
-I/home/kanze/libs/gabi-stable/include/conf/i80x86/linux/gcc3 
-I/home/kanze/libs/gabi-stable/include 
-I/home/kanze/libs/gabi-stable/sources/conf/i80x86/linux/gcc3 
-I/home/kanze/libs/gabi-stable/sources -L../lib 
-L/home/kanze/libs/gabi-stable/lib/i80x86/linux/gcc3 objects/testmain.o 
objects/libtest.a objects/libInput.a -lSystem -lUtil -lProcess-d -lIO-d 
-lText-d -lBasic-d -lTest-d -lPort-d -ldl -rdynamic

Logically, I don't think that this should play a role; there's
nothing in the main which uses the template in question.

--
James Kanze                                      home: www.gabi-soft.fr
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