I am trying to evaluate Intel C++ for Linux on a 64-bit Fedora 12 system. My application loads plug-ins (shared libraries) with dlopen. The dynamic loader should resolve symbols unresolved in the plug-in to symbols in the main executable. This works fine with g++ with no special options in building the executable or plug-ins.
I can load plug-ins built by icpc with a main executable built by g++, but when I try to load either flavor of plug-in from an executable built by icpc, I get unresolved symbols that are, in fact, defined in the main executable.
I am using icpc 11.1.064 and circumventing a bug by pointing to a g++ 4.2 compiler that is not the default (4.4.3). The compile options are these:
-march=core2 -m64 -fp-model precise -ansi -fPIC -fvisibility=default -gcc-name=/opt/gcc424/bin/gcc424 -gxx-name=/opt/gcc424/bin/g++424 -pthread -O2 -fno-strict-aliasing
The -fvisibility=default option was just a last effort to find something that might work.
There are no additional link options, except '-shared -Wl,-soname,foo' for the plug-ins.
What am I missing?
As you don't identify the unresolved symbols, but apparently they are associated with the recent g++, I guess you have run into a case where icpc doesn't fully support the recent g++ headers or libraries.
I don't believe icpc recognizes -ansi or strict-aliasing options, but it defaults to the equivalent of -fno-strict-aliasing, so it looks like you are OK there. Likewise, I don't think -march=core2 will be recognized as a synonym for -xSSSE3. A recent Core 2 would support -xSSE4.1.
My application loads plug-ins (shared libraries) with dlopen.
It is an lib personalized that you having wrote ? or is an standard lib that you can inform ?
void * handle = dlopen ("????????????",????????).
Your options (flag )compiler that you have wrote are perfectly correct,
just test with add (-shared-intel),I don't know is an possibility.
./icpc -fPIC -shared-intel
I found the source of my problem. I thought that I was linking with the same flags as with g++, but I was missing one: -Wl,--export-dynamic.
Thanks for the suggestions.