------- Comment #17 from howarth at nitro dot med dot uc dot edu 2009-09-23
18:40 -------
(In reply to comment #6)
>
> The hiding trick goes something like:
>
> #define NOT_HERE_BEFORE_10_6(sym) \
> extern const char sym##_tmp3 __asm("$ld$hide$os10.3$_" #sym ); \
> __attribute__((visibility("default"))) const char sym##_tmp3 = 0;
> \
>
Maybe we're thinking differently about this. For FSF gcc 4.5, I would think
that we would change LIB_SPEC to always link in the -lgcc_ext shared library.
After all, these additional symbols really should in the operative libgcc that
is linked in and always available. I am not a big fan of adding configure flags
that the user has to invoke in order to access the symbols in libgcc_ext (which
I though was Iain's approach). Also I don't see why the macro above has any
advantages over just using -unexported_symbols_list and the libgcc-10.5.ver
file. Wouldn't this create binaries that are completely portable from
10.4->10.5->10.6 as long as the user provided the libgcc_ext.dylib that they
were linked against?
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39888
