README
1
2XZ Utils on Windows
3===================
4
5Introduction
6
7 This document explains how to build XZ Utils for Microsoft Windows
8 using MinGW (Minimalist GNU for Windows).
9
10 This is currently experimental and has got very little testing.
11 No ABI stability is promised for liblzma.dll.
12
13
14Why MinGW
15
16 XZ Utils code is C99. It should be possible to compile at least
17 liblzma using any C99 compiler. Compiling the command line tools may
18 need a little extra work to get them built on new systems, because
19 they use some features that aren't standardized in POSIX.
20
21 MinGW is free software. MinGW runtime provides some functions that
22 made porting the command line tools easier. Most(?) of the MinGW
23 runtime, which gets linked into the resulting binaries, is in the
24 public domain.
25
26 While most C compilers nowadays support C99 well enough (including
27 most compilers for Windows), MSVC doesn't. It seems that Microsoft
28 has no plans to ever support C99. Thus, it is not possible to build
29 XZ Utils using MSVC without doing a lot of work to convert the code.
30 Using prebuilt liblzma from MSVC is possible though, since the
31 liblzma API headers are in C89 and contain some non-standard extra
32 hacks required by MSVC.
33
34
35Getting and Installing MinGW
36
37 You can download MinGW for 32-bit Windows from Sourceforge:
38
39 http://sourceforge.net/project/showfiles.php?group_id=2435
40
41 It is enough to pick Automated MinGW Installer and MSYS Base System.
42 Using the automated installer, select at least runtime, w32api,
43 core compiler, and MinGW make. From MSYS you actually need only
44 certain tools, but it is easiest to just install the whole MSYS.
45
46 To build for x86-64 version of Windows, you can download a snapshot
47 of MinGW targeting for 64-bit Windows:
48
49 http://sourceforge.net/project/showfiles.php?group_id=202880
50
51 You can use the 32-bit MSYS also for 64-bit build, since we don't
52 link against anything in MSYS, just use the tools from it. You may
53 use the make tool from 32-bit MinGW (mingw32-make.exe) although
54 probably the make.exe from MSYS works too.
55
56 Naturally you can pick the components manually, for example to try
57 the latest available GCC. It is also possible to use a cross-compiler
58 to build Windows binaries for example on GNU/Linux, or use Wine to
59 run the Windows binaries. However, these instructions focus on
60 building on Windows.
61
62
63Building for 32-bit Windows
64
65 Add MinGW and MSYS to PATH (adjust if you installed to non-default
66 location):
67
68 set PATH=C:\MinGW\bin;C:\MSYS\1.0\bin;%PATH%
69
70 Then it should be enough to just run mingw32-make in this directory
71 (the directory containing this README):
72
73 mingw32-make
74
75
76Building for 64-bit Windows
77
78 For 64-bit build the PATH has to point to 64-bit MinGW:
79
80 set PATH=C:\MinGW64\bin;C:\MSYS\1.0\bin;%PATH%
81
82 You need to pass W64=1 to mingw32-make (or make if you don't have
83 mingw32-make):
84
85 mingw32-make W64=1
86
87
88Additional Make Flags and Targets
89
90 You may want to try some additional optimizations, which may or
91 may not make the code faster (and may or may not hit possible
92 compiler bugs more easily):
93
94 mingw32-make CFLAGS="-O3 -fomit-frame-pointer -funroll-loops"
95
96 If you want to enable assertions (the assert() macro), use DEBUG=1.
97 You may want to disable optimizations too if you plan to actually
98 debug the code. Never use DEBUG=1 for production builds!
99
100 mingw32-make DEBUG=1 CFLAGS="-g -O0"
101
102 To copy the built binaries and required headers into a clean
103 directory, use the pkg target:
104
105 mingw32-make pkg
106
107 It first removes a possibly existing pkg directory, and then
108 recreates it with the required files.
109
110 TODO: The pkg target doesn't copy any license or other copyright
111 related information into the pkg directory.
112
113
114Creating an Import Library for MSVC
115
116 The included Makefile creates import library liblzma.a which works
117 only(?) with MinGW. To use liblzma.dll for MSVC, you need to create
118 liblzma.lib using the lib command from MSVC:
119
120 lib /def:liblzma.def /out:liblzma.lib /machine:ix86
121
122 On x86-64, the /machine argument has to naturally be changed:
123
124 lib /def:liblzma.def /out:liblzma.lib /machine:x64
125
126
127To Do
128
129 - Test Win64 support and add instructions about getting x86-64
130 version of MinGW.
131
132 - Creating the import library for other compilers/linkers
133
134 - Building with other compilers for Windows
135
136 - liblzma currently uses cdecl. Would stdcall be more compatible?
137
138 - Support building more size-optimized liblzma (the HAVE_SMALL
139 define and other things that are needed)
140
141 - Support selecting which parts of liblzma to build to make the
142 library even smaller.
143
144 - Use the configure script on Windows just like it is used on all
145 the other systems?
146
147
148Bugs
149
150 Report bugs to <lasse.collin@tukaani.org> (in English or Finnish).
151
152 Take into account that I don't have MSVC and I cannot very easily
153 test anything on Windows. As of writing, I have tried MinGW and the
154 resulting binaries only under 32-bit Wine.
155
156