Fix #1473: warn when fclose() is used as a while loop condition#8444
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francois-berder wants to merge 3 commits intocppcheck-opensource:mainfrom
Open
Fix #1473: warn when fclose() is used as a while loop condition#8444francois-berder wants to merge 3 commits intocppcheck-opensource:mainfrom
francois-berder wants to merge 3 commits intocppcheck-opensource:mainfrom
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…oop condition Using fclose() as a while loop condition closes the file on every iteration and operates on an already-closed file handle from the second iteration onward. Signed-off-by: Francois Berder <fberder@outlook.fr>
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danmar
reviewed
Apr 25, 2026
| " while (fclose(a)) {}\n" | ||
| "}"); | ||
| TODO_ASSERT_EQUALS("[test.cpp:3:5]: (error) Used file that is not opened. [useClosedFile]\n", "", errout_str()); | ||
| ASSERT_EQUALS("[test.cpp:3:12]: (error) Used file that is not opened. [useClosedFile]\n", errout_str()); |
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add a test that ensures there are no false positives if files are opened in the loop.
I think it's really weird to use a fclose call as a loop condition anyway..
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@danmar I added two more checks that should handle a few more FP. I noticed that it does not handle do-while and for loops correctly.
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I have now extended the check to handle do-while loops in my latest commit.
…while loop condition
…d as a while loop condition
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Using fclose() as a while loop condition closes the file on every iteration and operates on an already-closed file handle from the second iteration onward.