Joel Baker <[EMAIL PROTECTED]> writes: > I believe they're from the dynamic linker (ld.elf_so), in this case.
That would indicate that the dynamic linker does not know what .hidden symbols are, which is a problem on its own. > > We have to consider __dso_handle and __cxa_atexit separately. For > > __dso_handle, can you tell whether HAVE_GAS_HIDDEN is defined? > > [EMAIL PROTECTED]:/tmp/Build/gcc-3.2-HOLD/gcc-3.2-3.2ds0/src# find . -type f > | xargs grep HAVE_GAS_HIDDEN > ... > ./gcc/config/cris/cris.h:#define HAVE_GAS_HIDDEN 1 > > (All of the others are .in files for autoconf, ChangeLog entries, or > #ifdef macros in various .c files) Correct - and this is how they would be defined for your system: configure runs, determines whether or not your assembler supports hidden symbols, and then writes that information into gcc/auto-host.h of the build directory. Thus, looking at the sources won't help that much (I could have done that myself). > I will note that the __dso_handle references go away if __cxa_atexit is not > enabled. Correct - __dso_handle is only used together with __cxa_atexit. So if you decide not to use __cxa_atexit, you don't need to worry about __dso_handle. If you get a definition for __cxa_atexit, you'll have to come back and study the issue of .hidden symbols. > grep -i cxa /usr/src/lib/libc/stdlib/atexit.* returns nothing; I'm not sure > where else I would look, but that's not promising. That might well be the case - so far, only Linux provides that function, and perhaps HP-UX. > I can file a feature > request on it, but it won't show up in the stable tree until at least 1.6++ > (1.6 is at RC3 right now). Is there a simple spec, URL, or similar that I > can point at when filing the request? It's in the C++ ABI, at http://www.codesourcery.com/cxx-abi/abi.html#dso-dtor > Is this something that can be autoconfed or otherwise detected? This is tricky. You can try to come up with a test, but you need to test: - whether as/ld support .hidden symbols, - whether the dynamic linker correctly implements them, - whether the C library provides __cxa_atexit and __cxa_finalize. In gcc, since this is information about the target system (for which you can't run programs), such information is usually hard-coded in the machine descriptions. For __cxa_atexit, it used to be the case that end-users would need to add -fuse-cxa-atexit at g++ invocation time. The configure option was added only recently, and nobody has attempted to provide per-target defaults. Regards, Martin
