3.1 KiB
Troubleshooting
General issues
Diagram generated with PlantUML is cropped
When generating diagrams with PlantUML without specifying an output file format, the default is PNG. Unfortunately PlantUML will not check if the diagram will fit in the default PNG size, and often the diagram will be be incomplete in the picture. A better option is to specify SVG as output format and then convert to PNG, e.g.:
$ plantuml -tsvg mydiagram.puml
$ convert +antialias mydiagram.svg mydiagram.png
Class diagrams
"fatal error: 'stddef.h' file not found"
This error means that Clang cannot find some standard headers in the include paths
specified in the compile_commands.json. This typically happens on macos and sometimes on Linux, when
the code was compiled with different Clang version than clang-uml itself.
One solution to this issue is to add the following line to your CMakeLists.txt file:
set(CMAKE_CXX_STANDARD_INCLUDE_DIRECTORIES ${CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES})
Another option is to make sure that the Clang is installed on the system (even if not used for building your project), e.g.:
apt install clang
Sequence diagrams
Generated diagram is empty
In order to generate sequence diagram the start_from configuration option must have a valid starting point
for the diagram (e.g. function), which must match exactly the function signature in the clang-uml model.
Look for error in the console output such as:
Failed to find participant mynamespace::foo(int) for start_from condition
which means that either you have a typo in the function signature in the configuration file, or that the function
was not defined in the translation units you specified in the glob patterns for this diagram. Run again the
clang-uml tool with -vvv option and look in the console output for any mentions of the function from
which the diagram should start and copy the exact signature into the configuration file.
Generated diagram contains several empty control blocks or calls which should not be there
Currently the filtering of call expressions and purging empty control blocks (e.g. loops or conditional statements),
within which no interesting calls were included in the diagram is not perfect. In case the regular namespaces filter
is not enough, it is useful to add also a paths filter, which will only include participants and call expressions
from files in a subdirectory of your project, e.g.:
include:
namespaces:
- myproject
paths:
- src