Commit Graph

9 Commits

Author SHA1 Message Date
Michael Pratt
5f47ccc0ea tools/elfutils: do not directly link gnulib to libelf
The compiled library resulting from importing gnulib has been
linked to libelf in order to easily cover other link dependencies.
However, this is not appropriate for linking libelf to other programs
as it bloats the resulting libelf library, and may result in
multiple defintions of symbols based on whether or not
certain modules from gnulib are included while elfutils
already has it's own definition of a function.

This is not a problem while building elfutils, because gnulib has
it's own way of creating function aliases and special declarations
that allow the linker to ignore the original function definitions,
however, when libelf is used to link to something else,
this results in an error at link time.

The gnulib manual recommended linking the libraries directly,
but those who have written it may not have considered how this
can affect the ability to link that library in other builds,
they likely assume the build targets would not be a dependency.

Fix this by removing the linking between gnulib and libelf
and instead overriding Make variables in order to add linking
between gnulib and each of the binaries provided by elfutils,
using Make functions to avoid applying it to other subdirectories.

The function tdestroy() would still be missing on macOS,
but the existence of the gnulib tsearch object having been built
is an indicator of whether or not it is needed
because it is only built conditionally by gnulib,
so include linking that object only when it exists.

Block the unnecessary replacement of some functions by gnulib
so that future linking with libelf doesn't require
the associated gnulib "rpl" prefixed functions.
These replacements are very strict in order to correct
minor bugs that don't have a real impact in almost all cases
or new standards requirements that are not yet in effect or used.

Tested-by: Georgi Valkov <gvalkov@gmail.com> # macOS
Signed-off-by: Michael Pratt <mcpratt@pm.me>
Link: https://github.com/openwrt/openwrt/pull/15368
Signed-off-by: Robert Marko <robimarko@gmail.com>
2024-05-31 16:01:43 +02:00
Michael Pratt
7822908bf3 tools/elfutils: install a subset of the elfutils binaries
Install binaries that are not common with binutils
instead of none at all. This adds a negligible time to the build.

Building shared libraries is disabled, so the AM_LDFLAGS can be reset
without the rpath-link option which is unrecognized by clang.

Some of the binaries depend on functions that are defined
using a "strong alias" instead of a normal definition,
but this is disabled by our patches in order to work on macOS,
so use the identical function directly instead.

Add fnmatch from gnulib with GNU extensions
which is needed for usage of the FNM_EXTMATCH flag.

Handle a "Wunused-const-variable" error with the same
preprocessor conditional used to include the function
that the variable is used in.

Ref: f64bd4b6c ("tools/elfutils: only build required components")
Tested-by: Georgi Valkov <gvalkov@gmail.com> # macOS
Signed-off-by: Michael Pratt <mcpratt@pm.me>
Link: https://github.com/openwrt/openwrt/pull/15368
Signed-off-by: Robert Marko <robimarko@gmail.com>
2024-05-31 16:01:43 +02:00
Robert Marko
00ff73ec6e tools/elfutils: remove dirname
In the 0.191 update dirname was used instead of <libgen.h> to fix the
poisoned basename error:
/usr/include/libgen.h:35:9: error: attempt to use poisoned "basename"
       35 | #define basename        __xpg_basename

However, doing this has lead to libelf.a pulling in xmalloc, xstrdup and
friends and statically linking them thus leading to a symbol name conflict
with FRR host build and anything else that links against libelf and uses
xmalloc and friends.

Well, it turns out that upstream has added a helper[1] for basename so it
can compile with musl 1.2.5 which dropped the basename declaration, but it
also means that we must NOT include <libgen.h> and that poisoned error is
intentional and added to prevent duplicate basename definitions.
This also means that for macOS we dont need to do any additional header
inclusions as the new helper takes care of basename.

So, to fix the symbol conflict we can simply drop the <dirname.h> inclusion
and build from elfutils.

Tested on Fedora 40 as well as macOS 14.4.1.

[1] https://sourceware.org/git/?p=elfutils.git;a=commit;h=a2194f6b305bf0d0b9dd49dccd0a5c21994c8eea

Fixes: #24030
Fixes: b6f025b424 ("tools/elfutils: update to 1.91")

Link: https://github.com/openwrt/openwrt/pull/15337
Signed-off-by: Robert Marko <robimarko@gmail.com>
2024-04-30 13:37:59 +02:00
Michael Pratt
1991bfb814 tools/elfutils: refresh portability patch for macOS
Quilt refresh combined two sets of changes to the same file.

The switch from using libgen.h to dirname.h because of function poisoning
from gnulib's import of basename() was added as a new patch hunk instead
of an edit to the original one.

The original patch hunk was to fix build errors on an earlier version of
elfutils before the "dirname" module was being imported to fix further
build errors with the 0.191 version.

Tested-by: Georgi Valkov <gvalkov@gmail.com> # MacOS
Signed-off-by: Michael Pratt <mcpratt@pm.me>
Signed-off-by: Tony Ambardar <itugrok@yahoo.com>
2024-04-25 21:33:51 +02:00
Michael Pratt
ddb7177c57 tools/elfutils: remove no-op copy of tdestroy()
A false tdestroy() function was added in order to make elfutils build on
macOS again. A previous commit added declarations for a real version of
tdestroy() into gnulib, which is already imported, as well as the
preprocessor flags and the triggers for the Makefile.am conditional in
order to include the source to be built.

Tested-by: Georgi Valkov <gvalkov@gmail.com> # MacOS
Signed-off-by: Michael Pratt <mcpratt@pm.me>
Signed-off-by: Tony Ambardar <itugrok@yahoo.com>
2024-04-25 21:33:51 +02:00
Michael Pratt
7a4df7825e tools/elfutils: override SUBDIRS variable of Makefile
Instead of editing the SUBDIRS variable with a patch, it can be overriden
at the end of the command line when invoking Make.

This tool has a series of recursive Makefiles in each subdirectory,
therefore SUBDIRS is set to a pattern of Make functions so that the result
is variable depending on the current subdirectory that Make is being
invoked in.

It's not necessary to have gnulib-cache.m4 in EXTRA_DIST since we don't
need to re-import after packaging this in the SDK, so get rid of the
entire patch hunk for ./Makefile.am

Tested-by: Georgi Valkov <gvalkov@gmail.com> # MacOS
Signed-off-by: Michael Pratt <mcpratt@pm.me>
Signed-off-by: Tony Ambardar <itugrok@yahoo.com>
2024-04-25 21:33:51 +02:00
Tony Ambardar
b6f025b424 tools/elfutils: update to 1.91
Release Notes:
https://sourceware.org/pipermail/elfutils-devel/2024q1/006876.html

Manually refresh:
- 100-portability.patch

Change:
- replace libgen.h with gnulib "dirname" module for compilation errors:
    In file included from ./../libdw/libdwP.h:38,
                     from eblobjnote.c:42:
    /usr/include/libgen.h:35:9: error: attempt to use poisoned "basename"
       35 | #define basename        __xpg_basename
          |         ^

Tested-by: Georgi Valkov <gvalkov@gmail.com> # MacOS
Co-Developed-by: Nick Hainke <vincent@systemli.org>
Signed-off-by: Nick Hainke <vincent@systemli.org>
Signed-off-by: Tony Ambardar <itugrok@yahoo.com>
2024-04-25 21:33:51 +02:00
Felix Fietkau
f95a8f8769 tools/elfutils: fix missing _ in auxv info alias
Fixes dwarves compile issue

Signed-off-by: Felix Fietkau <nbd@nbd.name>
2023-11-01 19:20:35 +01:00
Felix Fietkau
5331e85d96 elfutils: fix build and enable on non-linux systems
Use gnulib for compatibility

Signed-off-by: Felix Fietkau <nbd@nbd.name>
2023-10-29 15:56:46 +01:00