1BEAR(1) BEAR(1)
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6 Bear - a tool to generate compilation database for Clang tooling.
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9 bear [options] -- [build command]
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12 The JSON compilation database <http://clang.llvm.org/docs/JSONCompila‐
13 tionDatabase.html> is used in Clang project to provide information how
14 a single compilation unit was processed. When that is available then
15 it is easy to re-run the compilation with different programs.
16 Bear executes the original build command and intercept the command exe‐
18 cutions issued by the build tool. From the log of command executions
19 it tries to identify the compiler calls and creates the final compila‐
20 tion database.
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23 --version
24 Print version number.
25 --help Print help message.
27 --verbose
29 Enable verbose logging.
30 --output file
32 Specify output file. (Default file name provided.) The output
33 is a JSON compilation database.
34 --append
36 Use previously generated output file and append the new entries
37 to it. This way you can run Bear continuously during work, and
38 it keeps the compilation database up to date. File deletion and
39 addition are both considered. But build process change (compil‐
40 er flags change) might cause duplicate entries.
41 --config file
43 Specify a configuration file. The configuration file captures
44 how the output should be formatted and which entries it shall
45 contain.
46 --force-preload
48 Force to use the dynamic linker method of intercept command.
49 --force-wrapper
51 Force to use the compiler wrapper method of intercept command.
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54 The JSON compilation database definition changed over time. The cur‐
55 rent version of Bear generates entries where:
56 directory
58 has absolute path.
59 file has absolute path.
61 output has absolute path.
63 arguments
65 used instead of command to avoid shell escaping problems. (Con‐
66 figuration can force to emit the command field.) The compiler as
67 the first argument has absolute path. Some non compilation re‐
68 lated flags are filtered out from the final output.
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71 Read citnames man page for the content of this file. bear is not read‐
72 ing the content of this file, but passing the file name to citnames.
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75 The exit status of the program is the exit status of the build command.
76 Except when the program itself crashes, then it sets to non-zero.
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79 The potential problems you can face with are: the build with and with‐
80 out Bear behaves differently or the output is empty.
81 The most common cause for empty outputs is that the build command did
83 not execute any commands. The reason for that could be, because incre‐
84 mental builds not running the compilers if everything is up-to-date.
85 Remember, Bear does not understand the build file (eg.: makefile), but
86 intercepts the executed commands.
87 The other common cause for empty output is that the build has a “con‐
89 figure” step, which captures the compiler to build the project. In
90 case of Bear is using the wrapper mode (read intercept man page), it
91 needs to run the configure step with Bear too (and discard that out‐
92 put), before run the build with Bear.
93 There could be many reasons for any of these failures. It’s better to
95 consult with the project wiki page for known problems, before open a
96 bug report.
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99 intercept(1), citnames(1)
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102 Copyright (C) 2012-2021 by László Nagy <https://github.com/rizsot‐
103 to/Bear>
104
106 László Nagy.
107Bear User Manuals Sep 04, 2021 BEAR(1)