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1 | This is a collection of tests for GDB. |
2 | ||
3 | The file gdb/README contains basic instructions on how to run the | |
4 | testsuite, while this file documents additional options and controls | |
5 | that are available. The GDB wiki may also have some pages with ideas | |
6 | and suggestions. | |
7 | ||
8 | ||
9 | Running the Testsuite | |
10 | ********************* | |
11 | ||
12 | There are two ways to run the testsuite and pass additional parameters | |
13 | to DejaGnu. The first is to do `make check' in the main build | |
14 | directory and specifying the makefile variable `RUNTESTFLAGS': | |
15 | ||
16 | make check RUNTESTFLAGS='TRANSCRIPT=y gdb.base/a2-run.exp' | |
17 | ||
18 | The second is to cd to the testsuite directory and invoke the DejaGnu | |
19 | `runtest' command directly. | |
20 | ||
21 | cd testsuite | |
22 | make site.exp | |
23 | runtest TRANSCRIPT=y | |
24 | ||
25 | (The `site.exp' file contains a handful of useful variables like host | |
26 | and target triplets, and pathnames.) | |
27 | ||
71c0c615 YQ |
28 | Running the Performance Tests |
29 | ***************************** | |
30 | ||
31 | GDB Testsuite includes performance test cases, which are not run together | |
32 | with other test cases, because performance test cases are slow and need | |
33 | a quiet system. There are two ways to run the performance test cases. | |
34 | The first is to do `make check-perf' in the main build directory: | |
35 | ||
36 | make check-perf RUNTESTFLAGS="solib.exp SOLIB_COUNT=8" | |
37 | ||
38 | The second is to cd to the testsuite directory and invoke the DejaGnu | |
39 | `runtest' command directly. | |
40 | ||
41 | cd testsuite | |
42 | make site.exp | |
43 | runtest GDB_PERFTEST_MODE=both GDB_PERFTEST_TIMEOUT=4000 --directory=gdb.perf solib.exp SOLIB_COUNT=8 | |
44 | ||
45 | Only "compile", "run" and "both" are valid to GDB_PERFTEST_MODE. They | |
46 | stand for "compile tests only", "run tests only", and "compile and run | |
47 | tests" respectively. "both" is the default. GDB_PERFTEST_TIMEOUT | |
48 | specify the timeout, which is 3000 in default. The result of | |
49 | performance test is appended in `testsuite/perftest.log'. | |
50 | ||
b866c52d SS |
51 | Testsuite Parameters |
52 | ******************** | |
53 | ||
54 | The following parameters are DejaGNU variables that you can set to | |
55 | affect the testsuite run globally. | |
56 | ||
57 | TRANSCRIPT | |
58 | ||
59 | You may find it useful to have a transcript of the commands that the | |
60 | testsuite sends to GDB, for instance if GDB crashes during the run, | |
61 | and you want to reconstruct the sequence of commands. | |
62 | ||
63 | If the DejaGNU variable TRANSCRIPT is set (to any value), each | |
64 | invocation of GDB during the test run will get a transcript file | |
65 | written into the DejaGNU output directory. The file will have the | |
66 | name transcript.<n>, where <n> is an integer. The first line of the | |
67 | file shows the invocation command with all the options passed to it, | |
68 | while subsequent lines are the GDB commands. A `make check' might | |
69 | look like this: | |
70 | ||
71 | make check RUNTESTFLAGS=TRANSCRIPT=y | |
72 | ||
73 | The transcript may not be complete, as for instance tests of command | |
74 | completion may show only partial command lines. | |
75 | ||
76 | GDB | |
77 | ||
78 | By default, the testsuite exercises the GDB in the build directory, | |
79 | but you can set GDB to be a pathname to a different version. For | |
80 | instance, | |
81 | ||
82 | make check RUNTESTFLAGS=GDB=/usr/bin/gdb | |
83 | ||
84 | runs the testsuite on the GDB in /usr/bin. | |
85 | ||
86 | GDBSERVER | |
87 | ||
88 | You can set GDBSERVER to be a particular GDBserver of interest, so for | |
89 | instance | |
90 | ||
91 | make check RUNTESTFLAGS="GDB=/usr/bin/gdb GDBSERVER=/usr/bin/gdbserver" | |
92 | ||
93 | checks both the installed GDB and GDBserver. | |
94 | ||
95 | INTERNAL_GDBFLAGS | |
96 | ||
97 | Command line options passed to all GDB invocations. | |
98 | ||
99 | The default is "-nw -nx". | |
100 | ||
101 | `-nw' disables any of the windowed interfaces. | |
102 | `-nx' disables ~/.gdbinit, so that it doesn't interfere with | |
103 | the tests. | |
104 | ||
105 | This is actually considered an internal variable, and you | |
106 | won't normally want to change it. However, in some situations, | |
107 | this may be tweaked as a last resort if the testsuite doesn't | |
108 | have direct support for the specifics of your environment. | |
109 | The testsuite does not override a value provided by the user. | |
110 | ||
111 | As an example, when testing an installed GDB that has been | |
112 | configured with `--with-system-gdbinit', like by default, | |
113 | you do not want ~/.gdbinit to interfere with tests, but, you | |
114 | may want the system .gdbinit file loaded. As there's no way to | |
115 | ask the testsuite, or GDB, to load the system gdbinit but | |
116 | not ~/.gdbinit, a workaround is then to remove `-nx' from | |
117 | INTERNAL_GDBFLAGS, and point $HOME at a directory without | |
118 | a .gdbinit. For example: | |
119 | ||
120 | cd testsuite | |
121 | HOME=`pwd` runtest \ | |
122 | GDB=/usr/bin/gdb \ | |
123 | GDBSERVER=/usr/bin/gdbserver \ | |
124 | INTERNAL_GDBFLAGS=-nw | |
125 | ||
126 | GDB_PARALLEL | |
127 | ||
128 | When testing natively (that is, not with a remote host), you can run | |
129 | the GDB test suite in a fully parallel mode. In this mode, each .exp | |
130 | file runs separately and maybe simultaneously. The test suite will | |
131 | ensure that all the temporary files created by the test suite do not | |
132 | clash, by putting them into separate directories. This mode is | |
133 | primarily intended for use by the Makefile. | |
134 | ||
135 | To use this mode, set the GDB_PARALLEL on the runtest command line. | |
136 | Before starting the tests, you must ensure that the directories cache, | |
137 | outputs, and temp in the test suite build directory are either empty | |
138 | or have been deleted. cache in particular is used to share data | |
139 | across invocations of runtest, and files there may affect the test | |
140 | results. Note that the Makefile automatically does these deletions. | |
141 | ||
142 | GDB_INOTIFY | |
143 | ||
144 | For debugging parallel mode, it is handy to be able to see when a test | |
145 | case writes to a file outside of its designated output directory. | |
146 | ||
147 | If you have the inotify-tools package installed, you can set the | |
148 | GDB_INOTIFY variable on the runtest command line. This will cause the | |
149 | test suite to watch for parallel-unsafe file creations and report | |
150 | them, both to stdout and in the test suite log file. | |
151 | ||
152 | This setting is only meaningful in conjunction with GDB_PARALLEL. | |
153 | ||
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154 | TESTS |
155 | ||
156 | This variable is used to specify which set of tests to run. | |
157 | It is passed to make (not runtest) and its contents are a space separated | |
158 | list of tests to run. | |
159 | ||
160 | If using GNU make then the contents are wildcard-expanded using | |
161 | GNU make's $(wildcard) function. Test paths must be fully specified, | |
162 | relative to the "testsuite" subdirectory. This allows one to run all | |
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163 | tests in a subdirectory by passing "gdb.subdir/*.exp", or more simply |
164 | by using the check-gdb.subdir target in the Makefile. | |
165 | ||
c17ef0d5 DE |
166 | If for some strange reason one wanted to run all tests that begin with |
167 | the letter "d" that is also possible: TESTS="*/d*.exp". | |
168 | ||
169 | Do not write */*.exp to specify all tests (assuming all tests are only | |
170 | nested one level deep, which is not necessarily true). This will pick up | |
171 | .exp files in ancillary directories like "lib" and "config". | |
172 | Instead write gdb.*/*.exp. | |
173 | ||
174 | Example: | |
175 | ||
176 | make -j10 check TESTS="gdb.server/[s-w]*.exp */x*.exp" | |
177 | ||
178 | If not using GNU make then the value is passed directly to runtest. | |
179 | If not specified, all tests are run. | |
b866c52d | 180 | |
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181 | READ1 |
182 | ||
183 | This make (not runtest) variable is used to specify whether the | |
184 | testsuite preloads the read1.so library into expect. Any non-empty | |
185 | value means true. See "Race detection" below. | |
186 | ||
187 | Race detection | |
188 | ************** | |
189 | ||
190 | The testsuite includes a mechanism that helps detect test races. | |
191 | ||
192 | For example, say the program running under expect outputs "abcd", and | |
193 | a test does something like this: | |
194 | ||
195 | expect { | |
196 | "a.*c" { | |
197 | } | |
198 | "b" { | |
199 | } | |
200 | "a" { | |
201 | } | |
202 | } | |
203 | ||
204 | Which case happens to match depends on what expect manages to read | |
205 | into its internal buffer in one go. If it manages to read three bytes | |
206 | or more, then the first case matches. If it manages to read two | |
207 | bytes, then the second case matches. If it manages to read only one | |
208 | byte, then the third case matches. | |
209 | ||
210 | To help detect these cases, the race detection mechanism preloads a | |
211 | library into expect that forces the `read' system call to always | |
212 | return at most 1 byte. | |
213 | ||
214 | To enable this, either pass a non-empty value in the READ1 make | |
215 | variable, or use the check-read1 make target instead of check. | |
216 | ||
217 | Examples: | |
218 | ||
219 | make -j10 check-read1 TESTS="*/paginate-*.exp" | |
220 | make -j10 check READ1="1" | |
221 | ||
b866c52d SS |
222 | Testsuite Configuration |
223 | *********************** | |
224 | ||
225 | It is possible to adjust the behavior of the testsuite by defining | |
226 | the global variables listed below, either in a `site.exp' file, | |
227 | or in a board file. | |
228 | ||
229 | gdb_test_timeout | |
230 | ||
231 | Defining this variable changes the default timeout duration used | |
232 | during communication with GDB. More specifically, the global variable | |
233 | used during testing is `timeout', but this variable gets reset to | |
234 | `gdb_test_timeout' at the beginning of each testcase, which ensures | |
235 | that any local change to `timeout' in a testcase does not affect | |
236 | subsequent testcases. | |
237 | ||
238 | This global variable comes in handy when the debugger is slower than | |
239 | normal due to the testing environment, triggering unexpected `TIMEOUT' | |
240 | test failures. Examples include when testing on a remote machine, or | |
241 | against a system where communications are slow. | |
242 | ||
243 | If not specifically defined, this variable gets automatically defined | |
244 | to the same value as `timeout' during the testsuite initialization. | |
245 | The default value of the timeout is defined in the file | |
246 | `testsuite/config/unix.exp' (at least for Unix hosts; board files may | |
247 | have their own values). | |
248 | ||
8b696e31 YQ |
249 | gdb_reverse_timeout |
250 | ||
251 | Defining this variable changes the default timeout duration when tests | |
252 | under gdb.reverse directory are running. Process record and reverse | |
253 | debugging is so slow that its tests have unexpected `TIMEOUT' test | |
254 | failures. This global variable is useful to bump up the value of | |
255 | `timeout' for gdb.reverse tests and doesn't cause any delay where | |
256 | actual failures happen in the rest of the testsuite. | |
257 | ||
b866c52d SS |
258 | |
259 | Board Settings | |
260 | ************** | |
261 | ||
262 | DejaGNU includes the concept of a "board file", which specifies | |
263 | testing details for a particular target (which are often bare circuit | |
264 | boards, thus the name). | |
265 | ||
266 | In the GDB testsuite specifically, the board file may include a | |
267 | number of "board settings" that test cases may check before deciding | |
268 | whether to exercise a particular feature. For instance, a board | |
269 | lacking any I/O devices, or perhaps simply having its I/O devices | |
270 | not wired up, should set `noinferiorio'. | |
271 | ||
272 | Here are the supported board settings: | |
273 | ||
274 | gdb,cannot_call_functions | |
275 | ||
276 | The board does not support inferior call, that is, invoking inferior | |
277 | functions in GDB. | |
278 | ||
279 | gdb,can_reverse | |
280 | ||
281 | The board supports reverse execution. | |
282 | ||
283 | gdb,no_hardware_watchpoints | |
284 | ||
285 | The board does not support hardware watchpoints. | |
286 | ||
287 | gdb,nofileio | |
288 | ||
289 | GDB is unable to intercept target file operations in remote and | |
290 | perform them on the host. | |
291 | ||
292 | gdb,noinferiorio | |
293 | ||
294 | The board is unable to provide I/O capability to the inferior. | |
295 | ||
296 | gdb,noresults | |
297 | ||
298 | A program will not return an exit code or result code (or the value | |
299 | of the result is undefined, and should not be looked at). | |
300 | ||
301 | gdb,nosignals | |
302 | ||
303 | The board does not support signals. | |
304 | ||
305 | gdb,skip_huge_test | |
306 | ||
307 | Skip time-consuming tests on the board with slow connection. | |
308 | ||
309 | gdb,skip_float_tests | |
310 | ||
311 | Skip tests related to floating point. | |
312 | ||
313 | gdb,use_precord | |
314 | ||
315 | The board supports process record. | |
316 | ||
a25eb028 MR |
317 | gdb_init_command |
318 | gdb_init_commands | |
319 | ||
320 | Commands to send to GDB every time a program is about to be run. The | |
321 | first of these settings defines a single command as a string. The | |
322 | second defines a TCL list of commands being a string each. The commands | |
323 | are sent one by one in a sequence, first from `gdb_init_command', if any, | |
324 | followed by individual commands from `gdb_init_command', if any, in this | |
325 | list's order. | |
326 | ||
b866c52d SS |
327 | gdb_server_prog |
328 | ||
329 | The location of GDBserver. If GDBserver somewhere other than its | |
330 | default location is used in test, specify the location of GDBserver in | |
331 | this variable. The location is a file name for GDBserver, and may be | |
332 | either absolute or relative to the testsuite subdirectory of the build | |
333 | directory. | |
334 | ||
335 | in_proc_agent | |
336 | ||
337 | The location of the in-process agent (used for fast tracepoints and | |
338 | other special tests). If the in-process agent of interest is anywhere | |
339 | other than its default location, set this variable. The location is a | |
340 | filename, and may be either absolute or relative to the testsuite | |
341 | subdirectory of the build directory. | |
342 | ||
343 | noargs | |
344 | ||
345 | GDB does not support argument passing for inferior. | |
346 | ||
347 | no_long_long | |
348 | ||
349 | The board does not support type long long. | |
350 | ||
351 | use_cygmon | |
352 | ||
353 | The board is running the monitor Cygmon. | |
354 | ||
355 | use_gdb_stub | |
356 | ||
357 | The tests are running with a GDB stub. | |
358 | ||
b477a5e6 PA |
359 | exit_is_reliable |
360 | ||
361 | Set to true if GDB can assume that letting the program run to end | |
362 | reliably results in program exits being reported as such, as opposed | |
363 | to, e.g., the program ending in an infinite loop or the board | |
364 | crashing/resetting. If not set, this defaults to $use_gdb_stub. In | |
365 | other words, native targets are assumed reliable by default, and | |
366 | remote stubs assumed unreliable. | |
367 | ||
b866c52d SS |
368 | gdb,predefined_tsv |
369 | ||
370 | The predefined trace state variables the board has. | |
371 | ||
f6512a69 SM |
372 | gdb,no_thread_names |
373 | ||
374 | The target doesn't support thread names. | |
b866c52d SS |
375 | |
376 | Testsuite Organization | |
377 | ********************** | |
378 | ||
379 | The testsuite is entirely contained in `gdb/testsuite'. The main | |
380 | directory of the testsuite includes some makefiles and configury, but | |
381 | these are minimal, and used for little besides cleaning up, since the | |
382 | tests themselves handle the compilation of the programs that GDB will | |
383 | run. | |
384 | ||
385 | The file `testsuite/lib/gdb.exp' contains common utility procs useful | |
386 | for all GDB tests, while the directory testsuite/config contains | |
387 | configuration-specific files, typically used for special-purpose | |
388 | definitions of procs like `gdb_load' and `gdb_start'. | |
389 | ||
390 | The tests themselves are to be found in directories named | |
391 | 'testsuite/gdb.* and subdirectories of those. The names of the test | |
392 | files must always end with ".exp". DejaGNU collects the test files by | |
393 | wildcarding in the test directories, so both subdirectories and | |
394 | individual files typically get chosen and run in alphabetical order. | |
395 | ||
396 | The following lists some notable types of subdirectories and what they | |
397 | are for. Since DejaGNU finds test files no matter where they are | |
398 | located, and since each test file sets up its own compilation and | |
399 | execution environment, this organization is simply for convenience and | |
400 | intelligibility. | |
401 | ||
402 | gdb.base | |
403 | ||
404 | This is the base testsuite. The tests in it should apply to all | |
405 | configurations of GDB (but generic native-only tests may live here). | |
406 | The test programs should be in the subset of C that is both valid | |
407 | ANSI/ISO C, and C++. | |
408 | ||
409 | gdb.<lang> | |
410 | ||
411 | Language-specific tests for any language besides C. Examples are | |
412 | gdb.cp for C++ and gdb.java for Java. | |
413 | ||
414 | gdb.<platform> | |
415 | ||
416 | Non-portable tests. The tests are specific to a specific | |
bc23328c | 417 | configuration (host or target), such as eCos. |
b866c52d SS |
418 | |
419 | gdb.arch | |
420 | ||
421 | Architecture-specific tests that are (usually) cross-platform. | |
422 | ||
423 | gdb.<subsystem> | |
424 | ||
425 | Tests that exercise a specific GDB subsystem in more depth. For | |
426 | instance, gdb.disasm exercises various disassemblers, while | |
427 | gdb.stabs tests pathways through the stabs symbol reader. | |
428 | ||
71c0c615 YQ |
429 | gdb.perf |
430 | ||
431 | GDB performance tests. | |
432 | ||
b866c52d SS |
433 | Writing Tests |
434 | ************* | |
435 | ||
436 | In many areas, the GDB tests are already quite comprehensive; you | |
437 | should be able to copy existing tests to handle new cases. Be aware | |
438 | that older tests may use obsolete practices but have not yet been | |
439 | updated. | |
440 | ||
441 | You should try to use `gdb_test' whenever possible, since it includes | |
442 | cases to handle all the unexpected errors that might happen. However, | |
443 | it doesn't cost anything to add new test procedures; for instance, | |
444 | gdb.base/exprs.exp defines a `test_expr' that calls `gdb_test' | |
445 | multiple times. | |
446 | ||
447 | Only use `send_gdb' and `gdb_expect' when absolutely necessary. Even | |
448 | if GDB has several valid responses to a command, you can use | |
449 | `gdb_test_multiple'. Like `gdb_test', `gdb_test_multiple' recognizes | |
450 | internal errors and unexpected prompts. | |
451 | ||
452 | Do not write tests which expect a literal tab character from GDB. On | |
453 | some operating systems (e.g. OpenBSD) the TTY layer expands tabs to | |
454 | spaces, so by the time GDB's output reaches `expect' the tab is gone. | |
455 | ||
456 | The source language programs do *not* need to be in a consistent | |
457 | style. Since GDB is used to debug programs written in many different | |
458 | styles, it's worth having a mix of styles in the testsuite; for | |
459 | instance, some GDB bugs involving the display of source lines might | |
460 | never manifest themselves if the test programs used GNU coding style | |
461 | uniformly. | |
462 | ||
463 | Some testcase results need more detailed explanation: | |
464 | ||
465 | KFAIL | |
466 | ||
467 | Use KFAIL for known problem of GDB itself. You must specify the GDB | |
468 | bug report number, as in these sample tests: | |
469 | ||
470 | kfail "gdb/13392" "continue to marker 2" | |
471 | ||
472 | or | |
473 | ||
474 | setup_kfail gdb/13392 "*-*-*" | |
475 | kfail "continue to marker 2" | |
476 | ||
477 | ||
478 | XFAIL | |
479 | ||
480 | Short for "expected failure", this indicates a known problem with the | |
481 | environment. This could include limitations of the operating system, | |
482 | compiler version, and other components. | |
483 | ||
484 | This example from gdb.base/attach-pie-misread.exp is a sanity check | |
485 | for the target environment: | |
486 | ||
487 | # On x86_64 it is commonly about 4MB. | |
488 | if {$stub_size > 25000000} { | |
489 | xfail "stub size $stub_size is too large" | |
490 | return | |
491 | } | |
492 | ||
493 | You should provide bug report number for the failing component of the | |
494 | environment, if such bug report is available, as with this example | |
495 | referring to a GCC problem: | |
496 | ||
497 | if {[test_compiler_info {gcc-[0-3]-*}] | |
498 | || [test_compiler_info {gcc-4-[0-5]-*}]} { | |
499 | setup_xfail "gcc/46955" *-*-* | |
500 | } | |
501 | gdb_test "python print ttype.template_argument(2)" "&C::c" | |
502 | ||
503 | Note that it is also acceptable, and often preferable, to avoid | |
504 | running the test at all. This is the better option if the limitation | |
505 | is intrinsic to the environment, rather than a bug expected to be | |
506 | fixed in the near future. |