diff options
| author | Thomas Petazzoni <thomas.petazzoni@free-electrons.com> | 2017-08-20 23:01:51 +0200 |
|---|---|---|
| committer | Thomas Petazzoni <thomas.petazzoni@free-electrons.com> | 2017-08-21 23:30:04 +0200 |
| commit | f4083db2eee229b689b5a8203ce2696d2b5e7212 (patch) | |
| tree | 46bc8efaefb4873ede92c685c93ec11324290a9e | |
| parent | d3c6db36227e315d13c0e8414f03d3f629572173 (diff) | |
| download | buildroot-f4083db2eee229b689b5a8203ce2696d2b5e7212.tar.gz buildroot-f4083db2eee229b689b5a8203ce2696d2b5e7212.zip | |
libunwind: needs dynamic library support
libunwind configure script explicitly links libunwind against
libgcc_s. libgcc_s is only guaranteed to be available for toolchains
that supports dynamic linking: pure static linking toolchains only
have libgcc.a, not libgcc_s.so.
Therefore, let's make libunwind unavailable on toolchains that lack
dynamic linking support. We could potentially support linking with
libgcc, but switching to libgcc_s was done upstream because libgcc was
lacking some symbols on ARM
(https://lists.nongnu.org/archive/html/libunwind-devel/2014-06/msg00024.html). Even
though recent gcc versions seem to provide such symbols in libgcc.a,
having libunwind available on static linking configurations is not a
useful enough use-case to do the necessary research to find when this
issue was fixed in gcc.
Since libunwind is not used as a mandatory dependency in any package,
adding this !BR2_STATIC_LIBS dependency is trivial and nicely avoids
the problematic situation.
This fixes two different autobuilder failures:
- Gstreamer 1.x programs failing to link, because libunwind links
against libgcc_s that isn't available (static linking
configuration):
http://autobuild.buildroot.net/results/9d4fbf7167e9afce0eef5c9e0cfd42c966ecba36/
- Gmrender-resurrect, which fails to link, because GStreamer 1.x uses
some libunwind functionality, but does not take into account the
libunwind dependency in its .pc files (static linking
configuration):
http://autobuild.buildroot.net/results/0a3a2485c187a000482c178f1e9c64dd716a858f/
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
| -rw-r--r-- | package/libunwind/Config.in | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/package/libunwind/Config.in b/package/libunwind/Config.in index 1a2531716f..be576d13c4 100644 --- a/package/libunwind/Config.in +++ b/package/libunwind/Config.in @@ -22,11 +22,14 @@ config BR2_PACKAGE_LIBUNWIND bool "libunwind" depends on BR2_TOOLCHAIN_HAS_THREADS depends on BR2_PACKAGE_LIBUNWIND_ARCH_SUPPORTS + # forcefully links against libgcc_s, only available in dynamic + # linking configurations + depends on !BR2_STATIC_LIBS help C API to determine the call-chain of a program. http://www.nongnu.org/libunwind/index.html -comment "libunwind needs a toolchain w/ threads" +comment "libunwind needs a toolchain w/ threads, dynamic library" depends on BR2_PACKAGE_LIBUNWIND_ARCH_SUPPORTS - depends on !BR2_TOOLCHAIN_HAS_THREADS + depends on !BR2_TOOLCHAIN_HAS_THREADS || BR2_STATIC_LIBS |
