README
1-*- mode: Outline -*-
2
3This is version 1.0 of the unwind library. This library supports
4several architecture/operating-system combinations:
5
6 Linux/x86-64: Works well.
7 Linux/x86: Works well.
8 Linux/ARM: Works well.
9 Linux/IA-64: Fully tested and supported.
10 Linux/PARISC: Works well, but C library missing unwind-info.
11 HP-UX/IA-64: Mostly works but known to have some serious limitations.
12 Linux/AArch64: Newly added.
13 Linux/PPC64: Newly added.
14 Linux/SuperH: Newly added.
15 FreeBSD/i386: Newly added.
16 FreeBSD/x86-64: Newly added (FreeBSD architecture is known as amd64).
17
18
19* General Build Instructions
20
21In general, this library can be built and installed with the following
22commands:
23
24 $ autoreconf -i # Needed only for building from git. Depends on libtool.
25 $ ./configure
26 $ make
27 $ make install prefix=PREFIX
28
29where PREFIX is the installation prefix. By default, a prefix of
30/usr/local is used, such that libunwind.a is installed in
31/usr/local/lib and unwind.h is installed in /usr/local/include. For
32testing, you may want to use a prefix of /usr/local instead.
33
34
35* Building with Intel compiler
36
37** Version 8 and later
38
39Starting with version 8, the preferred name for the IA-64 Intel
40compiler is "icc" (same name as on x86). Thus, the configure-line
41should look like this:
42
43 $ ./configure CC=icc CFLAGS="-g -O3 -ip" CXX=icc CCAS=gcc CCASFLAGS=-g \
44 LDFLAGS="-L$PWD/src/.libs"
45
46
47* Building on HP-UX
48
49For the time being, libunwind must be built with GCC on HP-UX.
50
51libunwind should be configured and installed on HP-UX like this:
52
53 $ ./configure CFLAGS="-g -O2 -mlp64" CXXFLAGS="-g -O2 -mlp64"
54
55Caveat: Unwinding of 32-bit (ILP32) binaries is not supported
56 at the moment.
57
58** Workaround for older versions of GCC
59
60GCC v3.0 and GCC v3.2 ship with a bad version of sys/types.h. The
61workaround is to issue the following commands before running
62"configure":
63
64 $ mkdir $top_dir/include/sys
65 $ cp /usr/include/sys/types.h $top_dir/include/sys
66
67GCC v3.3.2 or later have been fixed and do not require this
68workaround.
69
70* Building for PowerPC64 / Linux
71
72For building for power64 you should use:
73
74 $ ./configure CFLAGS="-g -O2 -m64" CXXFLAGS="-g -O2 -m64"
75
76If your power support altivec registers:
77 $ ./configure CFLAGS="-g -O2 -m64 -maltivec" CXXFLAGS="-g -O2 -m64 -maltivec"
78
79To check if your processor has support for vector registers (altivec):
80 cat /proc/cpuinfo | grep altivec
81and should have something like this:
82 cpu : PPC970, altivec supported
83
84If libunwind seems to not work (backtracing failing), try to compile
85it with -O0, without optimizations. There are some compiler problems
86depending on the version of your gcc.
87
88* Building on FreeBSD
89
90General building instructions apply. To build and execute several tests,
91you need libexecinfo library available in ports as devel/libexecinfo.
92
93Development of the port was done of FreeBSD 8.0-STABLE. The library
94was build with the system compiler that is modified version of gcc 4.2.1,
95as well as the gcc 4.4.3.
96
97* Regression Testing
98
99After building the library, you can run a set of regression tests with:
100
101 $ make check
102
103** Expected results on IA-64 Linux
104
105Unless you have a very recent C library and compiler installed, it is
106currently expected to have the following tests fail on IA-64 Linux:
107
108 Gtest-init (should pass starting with glibc-2.3.x/gcc-3.4)
109 Ltest-init (should pass starting with glibc-2.3.x/gcc-3.4)
110 test-ptrace (should pass starting with glibc-2.3.x/gcc-3.4)
111 run-ia64-test-dyn1 (should pass starting with glibc-2.3.x)
112
113This does not mean that libunwind cannot be used with older compilers
114or C libraries, it just means that for certain corner cases, unwinding
115will fail. Since they're corner cases, it is not likely for
116applications to trigger them.
117
118Note: If you get lots of errors in Gia64-test-nat and Lia64-test-nat, it's
119 almost certainly a sign of an old assembler. The GNU assembler used
120 to encode previous-stack-pointer-relative offsets incorrectly.
121 This bug was fixed on 21-Sep-2004 so any later assembler will be
122 fine.
123
124** Expected results on x86 Linux
125
126The following tests are expected to fail on x86 Linux:
127
128 Gtest-resume-sig (fails to get SIGUSR2)
129 Ltest-resume-sig (likewise)
130 Gtest-dyn1 (no dynamic unwind info support yet)
131 Ltest-dyn1 (no dynamic unwind info support yet)
132 test-setjmp (longjmp() not implemented yet)
133 run-check-namespace (no _Ux86_getcontext yet)
134 test-ptrace
135
136** Expected results on x86-64 Linux
137
138The following tests are expected to fail on x86-64 Linux:
139
140 Gtest-dyn1 (no dynamic unwind info support yet)
141 Ltest-dyn1 (no dynamic unwind info support yet)
142 Gtest-init (see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18743)
143 Ltest-init (likewise)
144 test-async-sig (crashes due to bad unwind-info?)
145 test-setjmp (longjmp() not implemented yet)
146 run-check-namespace (no _Ux86_64_getcontext yet)
147 run-ptrace-mapper (??? investigate)
148 run-ptrace-misc (see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18748
149 and http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18749)
150
151** Expected results on PARISC Linux
152
153Caveat: GCC v3.4 or newer is needed on PA-RISC Linux. Earlier
154versions of the compiler failed to generate the exception-handling
155program header (GNU_EH_FRAME) needed for unwinding.
156
157The following tests are expected to fail on x86-64 Linux:
158
159 Gtest-bt (backtrace truncated at kill() due to lack of unwind-info)
160 Ltest-bt (likewise)
161 Gtest-resume-sig (Gresume.c:my_rt_sigreturn() is wrong somehow)
162 Ltest-resume-sig (likewise)
163 Gtest-init (likewise)
164 Ltest-init (likewise)
165 Gtest-dyn1 (no dynamic unwind info support yet)
166 Ltest-dyn1 (no dynamic unwind info support yet)
167 test-setjmp (longjmp() not implemented yet)
168 run-check-namespace (toolchain doesn't support HIDDEN yet)
169
170** Expected results on HP-UX
171
172"make check" is currently unsupported for HP-UX. You can try to run
173it, but most tests will fail (and some may fail to terminate). The
174only test programs that are known to work at this time are:
175
176 tests/bt
177 tests/Gperf-simple
178 tests/test-proc-info
179 tests/test-static-link
180 tests/Gtest-init
181 tests/Ltest-init
182 tests/Gtest-resume-sig
183 tests/Ltest-resume-sig
184
185** Expected results on PPC64 Linux
186
187"make check" should run with no more than 10 out of 24 tests failed.
188
189
190* Performance Testing
191
192This distribution includes a few simple performance tests which give
193some idea of the basic cost of various libunwind operations. After
194building the library, you can run these tests with the following
195commands:
196
197 $ cd tests
198 $ make perf
199
200* Contacting the Developers
201
202Please direct all questions regarding this library to:
203
204 libunwind-devel@nongnu.org
205
206You can do this by sending a mail to libunwind-request@nongnu.org with
207a body of:
208
209 subscribe libunwind-devel
210
211or you can subscribe and manage your subscription via the
212web-interface at:
213
214 https://savannah.nongnu.org/mail/?group=libunwind
215