I think it's worthwhile to have a lint, but regexps are likely to have false positives, so using clang-tidy is probably better.
A bug is on file: https://bugzilla.mozilla.org/show_bug.cgi?id=1485588 On Mon, Aug 27, 2018 at 4:06 PM, Tom Ritter <t...@mozilla.com> wrote: > Is this something worth making a lint over? It's pretty easy to make > regex-based lints, e.g. > > yml-only based lint: > https://searchfox.org/mozilla-central/source/tools/lint/cpp-virtual-final.yml > > yml+python for slightly more complicated regexing: > https://searchfox.org/mozilla-central/source/tools/lint/mingw-capitalization.yml > https://searchfox.org/mozilla-central/source/tools/lint/cpp/mingw-capitalization.py > > -tom > > On Mon, Aug 27, 2018 at 7:04 AM, Henri Sivonen <hsivo...@mozilla.com> wrote: >> >> Please don't use the functions from ctype.h and strings.h. >> >> See: >> https://daniel.haxx.se/blog/2018/01/30/isalnum-is-not-my-friend/ >> https://daniel.haxx.se/blog/2008/10/15/strcasecmp-in-turkish/ >> >> https://stackoverflow.com/questions/2898228/can-isdigit-legitimately-be-locale-dependent-in-c >> >> In addition to these being locale-sensitive, the functions from >> ctype.h are defined to take (signed) int with the value space of >> *unsigned* char or EOF and other argument values are Undefined >> Behavior. Therefore, on platforms where char is signed, passing a char >> sign-extends to int and invokes UB if the most-significant bit of the >> char was set! Bug filed 15 years ago! >> https://bugzilla.mozilla.org/show_bug.cgi?id=216952 (I'm not aware of >> implementations doing anything surprising with this UB but there >> exists precedent for *compiler* writers looking at the standard >> *library* UB language and taking calls into standard library functions >> as optimization-guiding assertions about the values of their >> arguments, so better not risk it.) >> >> For isfoo(), please use mozilla::IsAsciiFoo() from mozilla/TextUtils.h. >> >> For tolower() and toupper(), please use ToLowerCaseASCII() and >> ToUpperCaseASCII() from nsUnicharUtils.h >> >> For strcasecmp() and strncasecmp(), please use their nsCRT::-prefixed >> versions from nsCRT.h. >> >> (Ideally, we should scrub these from vendored C code, too, since being >> in third-party code doesn't really make the above problems go away.) >> >> -- >> Henri Sivonen >> hsivo...@mozilla.com >> _______________________________________________ >> dev-platform mailing list >> dev-platform@lists.mozilla.org >> https://lists.mozilla.org/listinfo/dev-platform > > -- Henri Sivonen hsivo...@mozilla.com _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
