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cirras
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Sep 8, 2026
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Some feedback items to address, but this is looking great. Looking forward to getting this new rule into the analysis.
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Oops, I didn't mean to commit the test that failed CI. |
Raise statements have an optional `at expression` which should be accessible through the API.
cirras
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Sep 9, 2026
cirras
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Sep 10, 2026
A control flow graph is tied more closely to a statement list, rather than a routine implementation. That is because all statement lists can have a control flow graph, particularly `initialization` and `finalization` sections.
This provides the node the control flow graph was constructed from. This will allow consumers to reason about the surrounding context, e.g., subroutines, when using a `ControlFlowGraph`.
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Sep 11, 2026
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I think this is ready to go. Nice work!
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This PR implements #455.
There are two main parts to this PR. Other than the Check, nothing is slated to be added to the public API; everything remains internal.
1. Live variable analysis
The
BlockDataFlowVisitorinspects a single Block, notifying its call site of usages and assignments to variables.LocalDataFlowPropertiesrepresent what variables are assigned or used before assignment for a block. This is a fundamental building block for live variable analysis.LiveVariablescontain the information about which variables are alive coming in and going out of a given block. Additionally, there is some other information about the entire graph that comes in handy when implementing the dead store check.To support these changes, a
LiveVariableinterface was added to abstract across name declarations and references.2. Dead store check
This is the first check that uses variable liveness to add issues. High-level, this check raises issues on assignments of variables that aren't subsequently used, either by going out of scope or being reassigned.
Other changes
Some other changes were made in service of improving the modelling of control flow graphs.