CPP: Repair macro case.

geoffw0 · geoffw0 · commit 5b09e11a5224 · 2018-11-08T10:01:07.000Z
diff --git a/cpp/ql/src/Likely Bugs/Likely Typos/ExprHasNoEffect.ql b/cpp/ql/src/Likely Bugs/Likely Typos/ExprHasNoEffect.ql
@@ -99,6 +99,7 @@ where // EQExprs are covered by CompareWhereAssignMeant.ql
       not peivc.(FunctionCall).getTarget().hasName("operator==") and
       not accessInInitOfForStmt(peivc) and
       not peivc.isCompilerGenerated() and
+      not exists(Macro m | peivc = m.getAnInvocation().getAnExpandedElement()) and
       not peivc.isFromTemplateInstantiation(_) and
       parent = peivc.getParent() and
       not parent.isInMacroExpansion() and
diff --git a/cpp/ql/test/query-tests/Likely Bugs/Likely Typos/ExprHasNoEffect/ExprHasNoEffect.expected b/cpp/ql/test/query-tests/Likely Bugs/Likely Typos/ExprHasNoEffect/ExprHasNoEffect.expected
@@ -1,4 +1,3 @@
-| macros.c:6:9:6:13 | param | This expression has no effect. | macros.c:6:9:6:13 | param |  |
 | preproc.c:89:2:89:4 | call to fn4 | This expression has no effect (because $@ has no external side effects). | preproc.c:33:5:33:7 | fn4 | fn4 |
 | preproc.c:94:2:94:4 | call to fn9 | This expression has no effect (because $@ has no external side effects). | preproc.c:78:5:78:7 | fn9 | fn9 |
 | template.cpp:19:3:19:3 | call to operator++ | This expression has no effect (because $@ has no external side effects). | template.cpp:9:10:9:19 | operator++ | operator++ |
diff --git a/cpp/ql/test/query-tests/Likely Bugs/Likely Typos/ExprHasNoEffect/macros.c b/cpp/ql/test/query-tests/Likely Bugs/Likely Typos/ExprHasNoEffect/macros.c
@@ -3,5 +3,5 @@
 
 void test2(int param)
 {
-	UNUSED(param); // GOOD [FALSE POSITIVE]
+	UNUSED(param); // GOOD
 }

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,3 @@`
`1`		`-\| macros.c:6:9:6:13 \| param \| This expression has no effect. \| macros.c:6:9:6:13 \| param \| \|`
`2`	`1`	`\| preproc.c:89:2:89:4 \| call to fn4 \| This expression has no effect (because $@ has no external side effects). \| preproc.c:33:5:33:7 \| fn4 \| fn4 \|`
`3`	`2`	`\| preproc.c:94:2:94:4 \| call to fn9 \| This expression has no effect (because $@ has no external side effects). \| preproc.c:78:5:78:7 \| fn9 \| fn9 \|`
`4`	`3`	`\| template.cpp:19:3:19:3 \| call to operator++ \| This expression has no effect (because $@ has no external side effects). \| template.cpp:9:10:9:19 \| operator++ \| operator++ \|`
Original file line number	Diff line number	Diff line change
`@@ -3,5 +3,5 @@`
`3`	`3`
`4`	`4`	`void test2(int param)`
`5`	`5`	`{`
`6`		`- UNUSED(param); // GOOD [FALSE POSITIVE]`
	`6`	`+ UNUSED(param); // GOOD`
`7`	`7`	`}`