6a2552a141
This patch brings a fresh coat of paint to the LLDB website. This uses the `furo` theme from the suggested theme list, adds some changes to the css to make it use the full browser window width and removes the table of contents since the theme generates it automatically. This patch also rewrites the tables for "GDB to LLDB command map" to convert them from raw HTML to native inlined code blocks. To generate the website, make sure you install the theme first with `pip install furo`, enable sphinx in the cmake invocation` then run `ninja docs-lldb-html` Discourse: https://discourse.llvm.org/t/rfc-revamping-lldbs-website Differential Revision: https://reviews.llvm.org/D158323 Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
100 lines
3.7 KiB
ReStructuredText
100 lines
3.7 KiB
ReStructuredText
Troubleshooting
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===============
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File and Line Breakpoints Are Not Getting Hit
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---------------------------------------------
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First you must make sure that your source files were compiled with debug
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information. Typically this means passing -g to the compiler when compiling
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your source file.
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When setting breakpoints in implementation source files (.c, cpp, cxx, .m, .mm,
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etc), LLDB by default will only search for compile units whose filename
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matches. If your code does tricky things like using #include to include source
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files:
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::
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$ cat foo.c
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#include "bar.c"
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#include "baz.c"
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...
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This will cause breakpoints in "bar.c" to be inlined into the compile unit for
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"foo.c". If your code does this, or if your build system combines multiple
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files in some way such that breakpoints from one implementation file will be
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compiled into another implementation file, you will need to tell LLDB to always
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search for inlined breakpoint locations by adding the following line to your
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~/.lldbinit file:
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::
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$ echo "settings set target.inline-breakpoint-strategy always" >> ~/.lldbinit
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This tells LLDB to always look in all compile units and search for breakpoint
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locations by file and line even if the implementation file doesn't match.
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Setting breakpoints in header files always searches all compile units because
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inline functions are commonly defined in header files and often cause multiple
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breakpoints to have source line information that matches many header file
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paths.
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If you set a file and line breakpoint using a full path to the source file,
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like Xcode does when setting a breakpoint in its GUI on macOS when you click
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in the gutter of the source view, this path must match the full paths in the
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debug information. If the paths mismatch, possibly due to passing in a resolved
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source file path that doesn't match an unresolved path in the debug
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information, this can cause breakpoints to not be resolved. Try setting
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breakpoints using the file basename only.
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If you are using an IDE and you move your project in your file system and build
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again, sometimes doing a clean then build will solve the issue.This will fix
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the issue if some .o files didn't get rebuilt after the move as the .o files in
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the build folder might still contain stale debug information with the old
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source locations.
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How Do I Check If I Have Debug Symbols?
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---------------------------------------
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Checking if a module has any compile units (source files) is a good way to
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check if there is debug information in a module:
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::
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(lldb) file /tmp/a.out
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(lldb) image list
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[ 0] 71E5A649-8FEF-3887-9CED-D3EF8FC2FD6E 0x0000000100000000 /tmp/a.out
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/tmp/a.out.dSYM/Contents/Resources/DWARF/a.out
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[ 1] 6900F2BA-DB48-3B78-B668-58FC0CF6BCB8 0x00007fff5fc00000 /usr/lib/dyld
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....
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(lldb) script lldb.target.module['/tmp/a.out'].GetNumCompileUnits()
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1
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(lldb) script lldb.target.module['/usr/lib/dyld'].GetNumCompileUnits()
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0
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Above we can see that "/tmp/a.out" does have a compile unit, and
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"/usr/lib/dyld" does not.
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We can also list the full paths to all compile units for a module using python:
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::
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(lldb) script
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Python Interactive Interpreter. To exit, type 'quit()', 'exit()' or Ctrl-D.
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>>> m = lldb.target.module['a.out']
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>>> for i in range(m.GetNumCompileUnits()):
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... cu = m.GetCompileUnitAtIndex(i).file.fullpath
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/tmp/main.c
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/tmp/foo.c
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/tmp/bar.c
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>>>
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This can help to show the actual full path to the source files. Sometimes IDEs
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will set breakpoints by full paths where the path doesn't match the full path
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in the debug info and this can cause LLDB to not resolve breakpoints. You can
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use the breakpoint list command with the --verbose option to see the full paths
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for any source file and line breakpoints that the IDE set using:
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::
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(lldb) breakpoint list --verbose
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