On Tue, Dec 13, 2016 at 07:15:10AM -0500, Jeff King wrote: > I think these last two are a good sign that we need to be feeding the > list of source files to cppcheck. I tried your patch and it also started > looking in t/perf/build, which are old versions of git built to serve > the performance-testing suite. > > See the way that the "tags" target is handled for a possible approach.
Maybe something like this: diff --git a/Makefile b/Makefile index 8b5976d88..e7684ae63 100644 --- a/Makefile +++ b/Makefile @@ -2638,4 +2638,6 @@ cover_db_html: cover_db .PHONY: cppcheck cppcheck: - cppcheck --force --quiet --inline-suppr $(CPPCHECK_ADD) . + $(FIND_SOURCE_FILES) |\ + grep -v ^t/t |\ + xargs cppcheck --force --quiet --inline-suppr $(CPPCHECK_ADD) > My main complaint with any static checker is how we can handle false > positives. [...] Here's what that generates on my machine, with annotations: [builtin/am.c:766]: (error) Resource leak: in Correct. [builtin/notes.c:260]: (error) Memory pointed to by 'buf' is freed twice. [builtin/notes.c:264]: (error) Memory pointed to by 'buf' is freed twice. Nope. It appears not to understand that die() does not return. [builtin/rev-list.c:391]: (error) Uninitialized variable: reaches [builtin/rev-list.c:391]: (error) Uninitialized variable: all These are "int foo = foo" (which is ugly, and maybe we can get rid of if compilers have gotten smart enough to figure it out). [compat/nedmalloc/malloc.c.h:4646]: (error) Memory leak: mem Hard to tell, but I think this is wrong and is confused by pointer arithmetic on the malloc chunks. [compat/regex/regcomp.c:3086]: (error) Memory leak: sbcset Nope, this return is hit only when sbcset is NULL. The tool is presumably confused by a conditional hidden inside a macro. [compat/regex/regcomp.c:3634]: (error) Memory leak: sbcset [compat/regex/regcomp.c:3086]: (error) Memory leak: mbcset [compat/regex/regcomp.c:3634]: (error) Memory leak: mbcset I didn't look at these, but presumably similar. [compat/regex/regcomp.c:2802]: (error) Uninitialized variable: table_size [compat/regex/regcomp.c:2805]: (error) Uninitialized variable: table_size Not sure, but it looks like this function declares another inline function inside its scope, and that confuses the tool. [compat/regex/regcomp.c:532]: (error) Memory leak: fastmap Nope. Tool seems confused by hiding free() in a macro. [contrib/examples/builtin-fetch--tool.c:420]: (error) Uninitialized variable: lrr_count [contrib/examples/builtin-fetch--tool.c:427]: (error) Uninitialized variable: lrr_list More "int foo = foo". Might be worth omitting contrib/examples (or possibly contrib/ entirely) from the check. [t/helper/test-hashmap.c:125]: (error) Memory leak: entries [t/helper/test-hashmap.c:125]: (error) Memory leak: hashes Correct (but unimportant). So I think it is capable of finding real problems, but I think we'd need some way of squelching false positives, preferably in a way that carries forward as the code changes (so not just saying "foo.c:1234 is a false positive", which will break when it becomes "foo.c:1235"). -Peff
