Opened 10 years ago
Last modified 7 years ago
#2931 assigned defect
Bootstrapped compiler should check undefined variables in if branches
Reported by: | adrpo | Owned by: | adrpo |
---|---|---|---|
Priority: | high | Milestone: | Future |
Component: | MetaModelica | Version: | trunk |
Keywords: | Cc: |
Description (last modified by adrpo)
For example in CevalFunction.evaluateWhileStatement (modified on line 1438):
case (_, _, _, _, _, st) equation (cache, Values.BOOL(boolean = b), st) = cevalExp(inCondition, inCache, inEnv, st); if b then (cache, env, loop_ctrl, st) = evaluateStatements(inStatements, cache, inEnv, st); (cache, env, loop_ctrl, st) = evaluateWhileStatement(inCondition, inStatements, cache, env, loop_ctrl, st); else loop_ctrl = NEXT(); // env = inEnv; end if; then (cache, env, loop_ctrl, st);
env is not defined in the else branch.
This will compile code and for some models (i think it was MoistAir) will just crash.
Comment out env = inEnv; in the else branch and run the testsuite.
Change History (10)
comment:1 Changed 10 years ago by adrpo
- Description modified (diff)
comment:2 Changed 10 years ago by sjoelund.se
- Owner changed from sjoelund.se to adrpo
- Status changed from new to assigned
comment:3 Changed 10 years ago by perost
Here's a case where we get a false positive instead:
function test output Integer j; protected Boolean first := true; algorithm for i in {1, 2, 3} loop if first then j := i; first := false; else j := j + i; end if; end for; end test;
The compiler complains that j was used before given a value in the else-branch, but it does actually have a value since the first branch always runs first.
comment:4 Changed 9 years ago by sjoelund.se
- Milestone changed from 1.9.2 to 1.9.3
Milestone changed to 1.9.3 since 1.9.2 was released.
comment:5 Changed 9 years ago by sjoelund.se
- Milestone changed from 1.9.3 to 1.9.4
Moved to new milestone 1.9.4
comment:6 Changed 9 years ago by sjoelund.se
- Milestone changed from 1.9.4 to 1.9.5
Milestone pushed to 1.9.5
comment:7 Changed 9 years ago by sjoelund.se
- Milestone changed from 1.9.5 to 1.10.0
Milestone renamed
comment:8 Changed 8 years ago by sjoelund.se
- Milestone changed from 1.10.0 to 1.11.0
Ticket retargeted after milestone closed
comment:9 Changed 8 years ago by sjoelund.se
- Milestone changed from 1.11.0 to 1.12.0
Milestone moved to 1.12.0 due to 1.11.0 already being released.
comment:10 Changed 7 years ago by casella
- Milestone changed from 1.12.0 to Future
The milestone of this ticket has been reassigned to "Future".
If you think the issue is still valid and relevant for you, please select milestone 1.13.0 for back-end, code generation and run-time issues, or 2.0.0 for front-end issues.
If you are aware that the problem is no longer present, please select the milestone corresponding to the version of OMC you used to check that, and set the status to "worksforme".
In both cases, a short informative comment would be welcome.
The detection of assignment to uninitialised variables is conservative because the MSL uses the sort of patterns that are hard to detect if they are valid code (they are valid).