"visibility attribute not supported" gettext 0.17, Solaris 10, GCC 4.2.2

[Paul Eggert]

While compiling gettext 0.17 on Solaris 10 (sparc) with GCC 4.2.2, I
get lots of "visibility attribute not supported" diagnostics.  Here's
the first one:

        gcc -c -DLOCALEDIR=\"/r/share1/src/gettext/share/locale\" 
-DLOCALE_ALIAS_PATH=\"/r/share1/src/gettext/sha\re/locale\" 
-DLIBDIR=\"/r/share1/src/gettext/lib\" -DBUILDING_LIBINTL -DBUILDING_DLL 
-DIN_LIBINTL -DENABLE\_RELOCATABLE=1 -DIN_LIBRARY 
-DINSTALLDIR=\"/r/share1/src/gettext/lib\" -DNO_XMALLOC 
-Dset_relocation_prefi\x=libintl_set_relocation_prefix 
-Drelocate=libintl_relocate -DDEPENDS_ON_LIBICONV=1 -DHAVE_CONFIG_H -I. -I\. 
-I.. -D_REENTRANT -g -O2 -fvisibility=hidden ./finddomain.c  -fPIC -DPIC -o 
.libs/finddomain.o
        ./finddomain.c: In function '_nl_find_domain':
        ./finddomain.c:191: warning: visibility attribute not supported in this 
configuration; ignored

It's no big deal (I can ignore the messages).  But to avoid glitches
like this, perhaps gl_VISIBILITY should be changed to test whether the
visibility attribute works when linking, as opposed to just checking
whether it compiles?  That might makes sense anyway, as we might run
across buggy implementations where the visibility attribute actually
breaks linking.