Path: ...!news.mixmin.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Ben Bacarisse Newsgroups: comp.lang.c Subject: Re: question about nullptr Date: Tue, 09 Jul 2024 10:21:56 +0100 Organization: A noiseless patient Spider Lines: 41 Message-ID: <87bk36syx7.fsf@bsb.me.uk> References: <20240706054641.175@kylheku.com> <877cdyuq0f.fsf@bsb.me.uk> <2ckiO.19403$7Ej.4487@fx46.iad> <87plrpt4du.fsf@bsb.me.uk> <9bCiO.7108$sXW9.3805@fx41.iad> <87jzhwu5v9.fsf@bsb.me.uk> <20240708001722.280@kylheku.com> <878qyctcdt.fsf@bsb.me.uk> <20240708192708.531@kylheku.com> MIME-Version: 1.0 Content-Type: text/plain Injection-Date: Tue, 09 Jul 2024 11:21:56 +0200 (CEST) Injection-Info: dont-email.me; posting-host="3bc602097df9bef4fe534cf857153f79"; logging-data="1403793"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19YSX5VTok6UfOOPQn8BzSfIMyLTKo5TKk=" User-Agent: Gnus/5.13 (Gnus v5.13) Cancel-Lock: sha1:UTlyM8yjtrWdDzkKgs7HS+mnw9o= sha1:g2AUi7690Heb9ovM6BxiqKs2usE= X-BSB-Auth: 1.4eda8f48be124d053dde.20240709102156BST.87bk36syx7.fsf@bsb.me.uk Bytes: 3107 Kaz Kylheku <643-408-1753@kylheku.com> writes: > On 2024-07-08, Ben Bacarisse wrote: >> Janis Papanagnou writes: >> >>> On 08.07.2024 09:19, Kaz Kylheku wrote: >>>> On 2024-07-07, Ben Bacarisse wrote: >>>>> I find myself completely out of step with many posters here about >>>>> "explicit code" should look like. I think >>>>> >>>>> char *p = 0; >>>>> >>>>> is explicit enough and, in fact, I consider it a plus point if someone >>>>> reading it goes "hey, what's going on here?" and ends up learning that 0 >>>>> is null pointer constant in C. >>>> >>>> And if that person is on the C or C++ langauge committee, that bit of >>>> learning could just prevent a superfluous non-invention like nullptr. >>> >>> What's superfluous to one is useful for others (e.g. for grep'ing >>> occurrences of a null-pointer value in source codes); >> >> This is been suggested twice now but I'm struggling to see why that is >> useful. I can see management wanting one to find all uses of a null >> pointer constant to check that they have all been replaced by the >> "safer" nullptr, but what's the value in searching for nullptr? > > We could patch GCC to have a -Wnull-ptr-zero, which will give you a > diagnostic for every occurrence of a zero valued integer expression that > becomes a null pointer constant rather than an integer or floating-point > value (and that isn't cast to pointer type). Sure. I once tried to persuade the compiler team where I worked to write a "tool box" for diagnostics that would have a meta-language in which users could describe the conditions that wanted to be diagnosed. The idea was half-baked so it never went anywhere. -- Ben.