This semantic patch looks for variables that are initialized with a constant, are never updated, and are only used as parameter of return. Return the constant instead of using a variable.
There are 8 patches accepted reported by this semantic patch and more than 300 fixes to be applied. Signed-off-by: Peter Senna Tschudin <[email protected]> --- scripts/coccinelle/misc/returnvar.cocci | 66 +++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 scripts/coccinelle/misc/returnvar.cocci diff --git a/scripts/coccinelle/misc/returnvar.cocci b/scripts/coccinelle/misc/returnvar.cocci new file mode 100644 index 0000000..605955a --- /dev/null +++ b/scripts/coccinelle/misc/returnvar.cocci @@ -0,0 +1,66 @@ +/// +/// Removes unneeded variable used to store return value. +/// +// Confidence: Moderate +// Copyright: (C) 2012 Peter Senna Tschudin, INRIA/LIP6. GPLv2. +// URL: http://coccinelle.lip6.fr/ +// Comments: Comments on code can be deleted if near code that is removed. +// "when strict" can be removed to get more hits, but adds false +// positives +// Options: --no-includes --include-headers + +virtual patch +virtual report +virtual context +virtual org + +@depends on patch@ +type T; +constant C; +identifier ret; +@@ +- T ret = C; +... when != ret + when strict +return +- ret ++ C +; + +@depends on context@ +type T; +constant C; +identifier ret; +@@ +* T ret = C; +... when != ret + when strict +* return ret; + +@r1 depends on report || org@ +type T; +constant C; +identifier ret; +position p1, p2; +@@ +T ret@p1 = C; +... when != ret + when strict +return ret@p2; + +@script:python depends on report@ +p1 << r1.p1; +p2 << r1.p2; +C << r1.C; +ret << r1.ret; +@@ +coccilib.report.print_report(p1[0], "Unneeded variable: \"" + ret + "\". Return \"" + C + "\" on line " + p2[0].line) + +@script:python depends on org@ +p1 << r1.p1; +p2 << r1.p2; +C << r1.C; +ret << r1.ret; +@@ +cocci.print_main("unneeded \"" + ret + "\" variable", p1) +cocci.print_sec("return " + C + " here", p2) -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
