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This is version 1.0 of the unwind library. This library supports several architecture/operating-system combinations:
Linux/x86-64: Works well. Linux/x86: Works well. Linux/ARM: Works well. Linux/IA-64: Fully tested and supported. Linux/PARISC: Works well, but C library missing unwind-info. HP-UX/IA-64: Mostly works but known to have some serious limitations. Linux/AArch64: Newly added. Linux/PPC64: Newly added. Linux/SuperH: Newly added. FreeBSD/i386: Newly added. FreeBSD/x86-64: Newly added (FreeBSD architecture is known as amd64).
In general, this library can be built and installed with the following commands:
$ autoreconf -i # Needed only for building from git. Depends on libtool.
$ ./configure
$ make
$ make install prefix=PREFIXwhere PREFIX is the installation prefix. By default, a prefix of /usr/local is used, such that libunwind.a is installed in /usr/local/lib and unwind.h is installed in /usr/local/include. For testing, you may want to use a prefix of /usr/local instead.
** Version 8 and later
Starting with version 8, the preferred name for the IA-64 Intel compiler is "icc" (same name as on x86). Thus, the configure-line should look like this:
$ ./configure CC=icc CFLAGS="-g -O3 -ip" CXX=icc CCAS=gcc CCASFLAGS=-g \
LDFLAGS="-L$PWD/src/.libs"For the time being, libunwind must be built with GCC on HP-UX.
libunwind should be configured and installed on HP-UX like this:
$ ./configure CFLAGS="-g -O2 -mlp64" CXXFLAGS="-g -O2 -mlp64"Caveat: Unwinding of 32-bit (ILP32) binaries is not supported at the moment.
** Workaround for older versions of GCC
GCC v3.0 and GCC v3.2 ship with a bad version of sys/types.h. The workaround is to issue the following commands before running "configure":
$ mkdir $top_dir/include/sys
$ cp /usr/include/sys/types.h $top_dir/include/sysGCC v3.3.2 or later have been fixed and do not require this workaround.
For building for power64 you should use:
$ ./configure CFLAGS="-g -O2 -m64" CXXFLAGS="-g -O2 -m64"
If your power support altivec registers: $ ./configure CFLAGS="-g -O2 -m64 -maltivec" CXXFLAGS="-g -O2 -m64 -maltivec"
To check if your processor has support for vector registers (altivec): cat /proc/cpuinfo | grep altivec and should have something like this: cpu : PPC970, altivec supported
If libunwind seems to not work (backtracing failing), try to compile it with -O0, without optimizations. There are some compiler problems depending on the version of your gcc.
General building instructions apply. To build and execute several tests, you need libexecinfo library available in ports as devel/libexecinfo.
Development of the port was done of FreeBSD 8.0-STABLE. The library was build with the system compiler that is modified version of gcc 4.2.1, as well as the gcc 4.4.3.
After building the library, you can run a set of regression tests with:
$ make check** Expected results on IA-64 Linux
Unless you have a very recent C library and compiler installed, it is currently expected to have the following tests fail on IA-64 Linux:
Gtest-init (should pass starting with glibc-2.3.x/gcc-3.4)
Ltest-init (should pass starting with glibc-2.3.x/gcc-3.4)
test-ptrace (should pass starting with glibc-2.3.x/gcc-3.4)
run-ia64-test-dyn1 (should pass starting with glibc-2.3.x)This does not mean that libunwind cannot be used with older compilers or C libraries, it just means that for certain corner cases, unwinding will fail. Since they're corner cases, it is not likely for applications to trigger them.
Note: If you get lots of errors in Gia64-test-nat and Lia64-test-nat, it's almost certainly a sign of an old assembler. The GNU assembler used to encode previous-stack-pointer-relative offsets incorrectly. This bug was fixed on 21-Sep-2004 so any later assembler will be fine.
** Expected results on x86 Linux
The following tests are expected to fail on x86 Linux:
Gtest-resume-sig (fails to get SIGUSR2)
Ltest-resume-sig (likewise)
Gtest-dyn1 (no dynamic unwind info support yet)
Ltest-dyn1 (no dynamic unwind info support yet)
test-setjmp (longjmp() not implemented yet)
run-check-namespace (no _Ux86_getcontext yet)
test-ptrace** Expected results on x86-64 Linux
The following tests are expected to fail on x86-64 Linux:
Gtest-dyn1 (no dynamic unwind info support yet)
Ltest-dyn1 (no dynamic unwind info support yet)
Gtest-init (see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18743)
Ltest-init (likewise)
test-async-sig (crashes due to bad unwind-info?)
test-setjmp (longjmp() not implemented yet)
run-check-namespace (no _Ux86_64_getcontext yet)
run-ptrace-mapper (??? investigate)
run-ptrace-misc (see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18748
and http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18749)** Expected results on PARISC Linux
Caveat: GCC v3.4 or newer is needed on PA-RISC Linux. Earlier versions of the compiler failed to generate the exception-handling program header (GNU_EH_FRAME) needed for unwinding.
The following tests are expected to fail on x86-64 Linux:
Gtest-bt (backtrace truncated at kill() due to lack of unwind-info)
Ltest-bt (likewise)
Gtest-resume-sig (Gresume.c:my_rt_sigreturn() is wrong somehow)
Ltest-resume-sig (likewise)
Gtest-init (likewise)
Ltest-init (likewise)
Gtest-dyn1 (no dynamic unwind info support yet)
Ltest-dyn1 (no dynamic unwind info support yet)
test-setjmp (longjmp() not implemented yet)
run-check-namespace (toolchain doesn't support HIDDEN yet)** Expected results on HP-UX
"make check" is currently unsupported for HP-UX. You can try to run it, but most tests will fail (and some may fail to terminate). The only test programs that are known to work at this time are:
tests/bt
tests/Gperf-simple
tests/test-proc-info
tests/test-static-link
tests/Gtest-init
tests/Ltest-init
tests/Gtest-resume-sig
tests/Ltest-resume-sig** Expected results on PPC64 Linux
"make check" should run with no more than 10 out of 24 tests failed.
This distribution includes a few simple performance tests which give some idea of the basic cost of various libunwind operations. After building the library, you can run these tests with the following commands:
$ cd tests $ make perf
Please direct all questions regarding this library to:
libunwind-devel@nongnu.orgYou can do this by sending a mail to libunwind-request@nongnu.org with a body of:
subscribe libunwind-develor you can subscribe and manage your subscription via the web-interface at:
https://savannah.nongnu.org/mail/?group=libunwind