Fix EXP50-CPP

Author: MichaelRFairhurst

change_notes/2026-2-20-update-expression-sequencing.md

@@ -1,4 +1,5 @@
- - `A5-0-1` - `ExpressionShouldNotRelyONOrderOfEvaluation.ql`
+ - `A5-0-1`, `EXP50-CPP` - `ExpressionShouldNotRelyONOrderOfEvaluation.ql`, `DoNotDependOnTheOrderOfScalarObjectEvaluationForSideEffects.ql`:
    - Fixed a bug where some sequenced operations were not detected as such due to an error in the "candidate selection" process. This could have complex effects on results, but should mostly fix false positives.
- - `RULE-13-2`, `A5-0-1` - `UnsequencedSideEffects.ql`, `UnsequencedAtomicReads.ql`, `ExpressionShouldNotRelyONOrderOfEvaluation.ql`
+   - Some unsequenced operations that previously reported one alert may now report two, due to the extra candidates being considered.
+ - `RULE-13-2`, `A5-0-1`, `EXP50-CPP` - `UnsequencedSideEffects.ql`, `UnsequencedAtomicReads.ql`, `ExpressionShouldNotRelyONOrderOfEvaluation.ql`, `DoNotDependOnTheOrderOfScalarObjectEvaluationForSideEffects.ql`:
    - Implementation of ordering has been refactored to share more code across specifications (C11-C17, C++14, and C++17 sequencing rules). No change in results is expected from this refactor.

cpp/cert/src/rules/EXP50-CPP/DoNotDependOnTheOrderOfScalarObjectEvaluationForSideEffects.ql

@@ -23,16 +23,15 @@ import codingstandards.cpp.Ordering
 import codingstandards.cpp.orderofevaluation.VariableAccessOrdering
 import codingstandards.cpp.Expr
 import codingstandards.cpp.Variable
+import Ordering::Make<Cpp14VariableAccessInFullExpressionOrdering> as FullExprOrdering
 
-from
-  VariableAccessInFullExpressionOrdering config, FullExpr e, ScalarVariable v, VariableEffect ve,
-  VariableAccess va1, VariableAccess va2
+from FullExpr e, ScalarVariable v, VariableEffect ve, VariableAccess va1, VariableAccess va2
 where
   not isExcluded(e,
     SideEffects1Package::doNotDependOnTheOrderOfScalarObjectEvaluationForSideEffectsQuery()) and
   e = va1.(ConstituentExpr).getFullExpr() and
   va1 = ve.getAnAccess() and
-  config.isUnsequenced(va1, va2) and
+  FullExprOrdering::isUnsequenced(va1, va2) and
   v = va1.getTarget()
 select e, "Scalar object referenced by $@ has a $@ that is unsequenced in relative to another $@.",
   v, v.getName(), ve, "side-effect", va2, "side-effect or value computation"

cpp/cert/test/rules/EXP50-CPP/DoNotDependOnTheOrderOfScalarObjectEvaluationForSideEffects.expected

@@ -1,6 +1,9 @@
+| test.cpp:8:3:9:8 | ... = ... | Scalar object referenced by $@ has a $@ that is unsequenced in relative to another $@. | test.cpp:4:5:4:6 | g1 | g1 | test.cpp:8:3:9:8 | ... = ... | side-effect | test.cpp:8:10:8:11 | g1 | side-effect or value computation |
 | test.cpp:8:3:9:8 | ... = ... | Scalar object referenced by $@ has a $@ that is unsequenced in relative to another $@. | test.cpp:4:5:4:6 | g1 | g1 | test.cpp:8:8:8:11 | ++ ... | side-effect | test.cpp:8:3:8:4 | g1 | side-effect or value computation |
 | test.cpp:10:3:10:15 | ... = ... | Scalar object referenced by $@ has a $@ that is unsequenced in relative to another $@. | test.cpp:4:5:4:6 | g1 | g1 | test.cpp:10:6:10:9 | ... ++ | side-effect | test.cpp:10:14:10:15 | g1 | side-effect or value computation |
+| test.cpp:14:3:14:12 | ... += ... | Scalar object referenced by $@ has a $@ that is unsequenced in relative to another $@. | test.cpp:4:5:4:6 | g1 | g1 | test.cpp:14:3:14:12 | ... += ... | side-effect | test.cpp:14:9:14:10 | g1 | side-effect or value computation |
 | test.cpp:14:3:14:12 | ... += ... | Scalar object referenced by $@ has a $@ that is unsequenced in relative to another $@. | test.cpp:4:5:4:6 | g1 | g1 | test.cpp:14:9:14:12 | ... ++ | side-effect | test.cpp:14:3:14:4 | g1 | side-effect or value computation |
+| test.cpp:15:3:16:11 | ... = ... | Scalar object referenced by $@ has a $@ that is unsequenced in relative to another $@. | test.cpp:4:5:4:6 | g1 | g1 | test.cpp:15:3:16:11 | ... = ... | side-effect | test.cpp:15:8:15:9 | g1 | side-effect or value computation |
 | test.cpp:15:3:16:11 | ... = ... | Scalar object referenced by $@ has a $@ that is unsequenced in relative to another $@. | test.cpp:4:5:4:6 | g1 | g1 | test.cpp:15:8:16:11 | ... += ... | side-effect | test.cpp:15:3:15:4 | g1 | side-effect or value computation |
 | test.cpp:21:3:21:4 | call to f2 | Scalar object referenced by $@ has a $@ that is unsequenced in relative to another $@. | test.cpp:20:13:20:14 | p1 | p1 | test.cpp:21:6:21:9 | ... ++ | side-effect | test.cpp:21:12:21:13 | p1 | side-effect or value computation |
 | test.cpp:28:13:28:13 | call to operator<< | Scalar object referenced by $@ has a $@ that is unsequenced in relative to another $@. | test.cpp:26:13:26:14 | p1 | p1 | test.cpp:27:16:27:19 | ... ++ | side-effect | test.cpp:27:24:27:25 | p1 | side-effect or value computation |