C++: Accept test changes after github/codeql#21313.

[MathiasVP]

Description

In github/codeql#21313 we fixed a performance problem in SimpleRangeAnalysis. As part of that we reduced the limit for when range analysis decides to bail out and reduces precision because it expects too many bounds prior to the main range analysis recursion.

Because this test function produces so many bounds (because it's thousands of lines of code with lots of sequential ìfs) we now hit this limit.

I suggest you rewrite this test in the future to better reflect real-world code. This will make range analysis perform just like it did before.

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[Copilot]

Pull request overview

This PR updates the INT34-C C/CERT test expectations to account for the reduced precision behavior introduced by the SimpleRangeAnalysis performance fix (github/codeql#21313), ensuring the test suite continues to pass under the new analysis limits.

Changes:

• Mark two previously-COMPLIANT shift cases as expected false positives in INT34-C/test.c.
• Update the .expected baseline to reflect less precise (higher) inferred upper bounds from range analysis.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
c/cert/test/rules/INT34-C/test.c	Adjusts compliance annotations for two shift cases that now trigger alerts due to reduced range-analysis precision.
c/cert/test/rules/INT34-C/ExprShiftedbyNegativeOrGreaterPrecisionOperand.expected	Updates expected query results/upper-bound values (and adds any newly-triggered results) to match current analysis output.

Comments suppressed due to low confidence (1)

c/cert/test/rules/INT34-C/test.c:361

• Test markers elsewhere in this repo predominantly use underscore-separated tags like COMPLIANT[FALSE_POSITIVE]/NON_COMPLIANT[FALSE_NEGATIVE]. To keep consistency (and avoid any tooling that might treat spaces inside the tag unexpectedly), consider changing COMPLIANT[FALSE POSITIVE] to COMPLIANT[FALSE_POSITIVE] here.

  lhs12 << rhs13; // COMPLIANT[FALSE POSITIVE]: lhs12's precision is strictly greater than rhs13 (FP because range analysis reduced precision for performance reasons)
  lhs12 << rhs14; // COMPLIANT[FALSE POSITIVE]: lhs12's precision is strictly greater than rhs14 (FP because range analysis reduced precision for performance reasons)

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[paldepind]

Changes looks good to me.

Note that the actual simple range analysis produces a small number of bounds in this file. So there's a discrepancy between our estimate on the number of bounds and the actual numbers of bounds. I have an idea that might fix that and allow us to revert these changes later.

If that does not work out, another fix would be to split this up into several functions/introduce more variables such that the same variable is not used in as many if statements.