[Cocci] [PATCH] Coccinelle: doubletest: reduce side effect false positives

[Julia Lawall]

Ensure that the cited expression is not a function call or an
assignment to reduce the chance of false positives.

Slightly modify the warning message to indicate another source
of false positves.

Signed-off-by: Julia Lawall <***@lip6.fr>

---
scripts/coccinelle/tests/doubletest.cocci | 34 ++++++++++++++++++++++--------
1 file changed, 26 insertions(+), 8 deletions(-)

diff --git a/scripts/coccinelle/tests/doubletest.cocci b/scripts/coccinelle/tests/doubletest.cocci
index 78d74c2..7af2ce7 100644
--- a/scripts/coccinelle/tests/doubletest.cocci
+++ b/scripts/coccinelle/tests/doubletest.cocci
@@ -1,6 +1,7 @@
/// Find &&/|| operations that include the same argument more than once
-//# A common source of false positives is when the argument performs a side
-//# effect.
+//# A common source of false positives is when the expression, or
+//# another expresssion in the same && or || operation, performs a
+//# side effect.
///
// Confidence: Moderate
// Copyright: (C) 2010 Nicolas Palix, DIKU. GPLv2.
@@ -20,20 +21,37 @@ position p;
@@

(
-* ***@p
- || ... || E
+ ***@p || ... || E
|
-* ***@p
- && ... && E
+ ***@p && ... && E
)

-@script:python depends on org@
+@bad@
+expression r.E,e1,e2,fn;
+position r.p;
+assignment operator op;
+@@
+
+(
+***@p
+&
+ <+... \(fn(...)\|e1 op e2\|e1++\|e1--\|++e1\|--e1\) ...+>
+)
+
+@depends on context && !bad@
+expression r.E;
+position r.p;
+@@
+
+****@p
+
+@script:python depends on org && !bad@
p << r.p;
@@

cocci.print_main("duplicated argument to && or ||",p)

-@script:python depends on report@
+@script:python depends on report && !bad@
p << r.p;
@@

[Masahiro Yamada]

Post by Julia Lawall
Ensure that the cited expression is not a function call or an
assignment to reduce the chance of false positives.
Slightly modify the warning message to indicate another source
of false positves.

Applied to linux-kbuild. Thanks!


(Please send a reminder
if there are more coccinelle patches I missed.)

Post by Julia Lawall
---
scripts/coccinelle/tests/doubletest.cocci | 34 ++++++++++++++++++++++--------
1 file changed, 26 insertions(+), 8 deletions(-)
diff --git a/scripts/coccinelle/tests/doubletest.cocci b/scripts/coccinelle/tests/doubletest.cocci
index 78d74c2..7af2ce7 100644
--- a/scripts/coccinelle/tests/doubletest.cocci
+++ b/scripts/coccinelle/tests/doubletest.cocci
@@ -1,6 +1,7 @@
/// Find &&/|| operations that include the same argument more than once
-//# A common source of false positives is when the argument performs a side
-//# effect.
+//# A common source of false positives is when the expression, or
+//# another expresssion in the same && or || operation, performs a
+//# side effect.
///
// Confidence: Moderate
// Copyright: (C) 2010 Nicolas Palix, DIKU. GPLv2.
@@ -20,20 +21,37 @@ position p;
@@
(
- || ... || E
|
- && ... && E
)
+expression r.E,e1,e2,fn;
+position r.p;
+assignment operator op;
+
+(
+&
+ <+... \(fn(...)\|e1 op e2\|e1++\|e1--\|++e1\|--e1\) ...+>
+)
+
+expression r.E;
+position r.p;
+
+
p << r.p;
@@
cocci.print_main("duplicated argument to && or ||",p)
p << r.p;
@@