Robert Collins wrote:
libmingwex -- maybe. I dunno -- that's for Danny and/or Earnie to say. You really only need library-name based protection for static libs; symbols in import libs are protected from re-export by symbol-exclude lists (_nm_*,__imp__*, etc). libmsvcrt, libmingwthrd -- no (because they are implibs).
A light just went on. We could use a "exclude system archive" flag - dont' export symbols originating from libraries in /usr/local/lib/* or /usr/lib/* ( and possibly the gcc lib dir as well - although I think that is a spec thing, as it's gcc's decision to have the library given a certain name). Whaddya think?
I don't know if we have enough information in the auto_export() context. Here's what I found doing a simple link [ printing abfd->my->archive->filename when in auto_export() ]. Each line corresponds to a given symbol under consideration for auto-export (not shown)
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../libcygwin.a
abfd->my_arc->filename=/usr/lib/w32api/libkernel32.a
abfd->my_arc->filename=/usr/lib/w32api/libkernel32.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
abfd->my_arc->filename=/usr/lib/gcc-lib/i686-pc-cygwin/3.2/libgcc.a
First, how does ld know about gcc's built in path /usr/lib/gcc-lib/i686-pc-cygwin/3.2/ ?. Second, we'd have to canonicalize /usr/lib/gcc-lib/i686-pc-cygwin/3.2/../../../ to determine if it corresponded to the "system path" /usr/lib/ (which would be a nice trick on a cross-compiler setup)
The good news is that almost everything in /usr/lib/w32api/ is an import lib, so those symbols are not re-exported anyway...exceptions:
/usr/lib/w32api/libdxguid.a: x86 archive static
/usr/lib/w32api/liblargeint.a: x86 archive static
/usr/lib/w32api/libscrnsave.a: x86 archive static
/usr/lib/w32api/libscrnsavw.a: x86 archive static
So at least we needn't worry overmuch about ../w32api/..
But, I think it's overkill to define "system libs that should not be re-exported" as "anything in /usr/lib" or something similarly broad.
Perhaps the "regular" gcc-supplied system libs (libgcc, libstdc++, libsupc++, etc) can be explicitly rejected by name from within the ld.exe code, but additional **platform** dependent static runtime libraries like libmingwex, etc should actually be controlled by the platform-specific gcc spec file, using
--exclude-libs libmingwex.a,libcygwin.a,...
-----------------------------------------------------------------
On the other hand, we're really arguing about a problem that hasn't bit anyone yet. By excluding the main (gcc) static runtime libs from re-export, and the main (platform) static runtime libs like libmingw32 libmingwex from re-export -- we pretty much cover all the important bases.
Anything else is obviously a corner case, since it hasn't bit anyone yet -- and the fix is for that person to specifically exclude the static lib that "bit" them by using --exclude-libs.
The problem here, is that because of our packaging of gcc-2, we're missing the names of the (gcc) static runtime libs for that "package". Plus, libmingwex is another (platform) static runtime lib that we're missing -- but it was only recently added to the mingw "platform".
(I raised the issue of libtextmode & friends, but since the only "re-exportable" symbol in them is _cygwin_premain0 which is already excluded by autofilter_symbolprefixlist, there's no problem there.)
I think the (newly revised) attached patch is sufficient, and is general enough to be submitted for inclusion in the mainline binutils CVS.
--Chuck
Index: pe-dll.c
===================================================================
RCS file: /cvs/src/src/ld/pe-dll.c,v
retrieving revision 1.45
diff -u -r1.45 pe-dll.c
--- pe-dll.c 6 Nov 2002 19:36:20 -0000 1.45
+++ pe-dll.c 10 Nov 2002 01:30:02 -0000
@@ -228,12 +229,14 @@
/* Do not specify library suffix explicitly, to allow for dllized versions. */
static autofilter_entry_type autofilter_liblist[] =
{
- { "libgcc.", 7 },
- { "libstdc++.", 10 },
- { "libmingw32.", 11 },
- { "libg2c.", 7 },
- { "libsupc++.", 10 },
- { "libobjc.", 8 },
+ { "libgcc", 6 },
+ { "libstdc++", 9 },
+ { "libmingw32", 10 },
+ { "libmingwex", 10 },
+ { "libg2c", 6 },
+ { "libsupc++", 9 },
+ { "libobjc", 7 },
+ { "libgcj", 6 },
{ NULL, 0 }
};
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