Path: csiph.com!eternal-september.org!feeder.eternal-september.org!nntp.eternal-september.org!.POSTED!not-for-mail From: Keith Thompson Newsgroups: comp.lang.c Subject: Re: printf and time_t Date: Mon, 12 Jan 2026 16:06:08 -0800 Organization: None to speak of Lines: 25 Message-ID: <87h5sqpea7.fsf@example.invalid> References: <10jfol6$2u6r8$1@news.xmission.com> <10jhkso$3c9r2$3@nntp.eternal-september.org> <20260106112938.00004446@yahoo.com> <10jj9st$3jbe4$2@dont-email.me> <20260106200522.000015ea@yahoo.com> <87h5sy2rlb.fsf@example.invalid> <87qzs1gliq.fsf@example.invalid> <20260108012620.000041a9@yahoo.com> <87bjj5gei4.fsf@example.invalid> <20260108023846.0000260c@yahoo.com> <10jpi8h$15aea$1@dont-email.me> <20260109141859.00004f22@yahoo.com> <10jv3rb$15aea$2@dont-email.me> <20260111132015.000026ad@yahoo.com> <87ikd82tks.fsf@example.invalid> <20260111153201.000075f9@yahoo.com> <87ecnv3gj2.fsf@example.invalid> <10k27e7$25sqv$1@dont-email.me> <20260112110648.00002626@yahoo.com> <10k2pa0$2al6k$1@dont-email.me> MIME-Version: 1.0 Content-Type: text/plain Injection-Date: Tue, 13 Jan 2026 00:06:09 +0000 (UTC) Injection-Info: dont-email.me; posting-host="0e64289da795cda92cb4be4d5bbb82c9"; logging-data="2901392"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18gNo/UH4OZglw1JOwdQ4q3" User-Agent: Gnus/5.13 (Gnus v5.13) Cancel-Lock: sha1:m+SfLSlcOpuNWyBtIZmeIdXomHI= sha1:Q7JPtGgxeoraQca662e6LuWRanM= Xref: csiph.com comp.lang.c:396381 David Brown writes: [...] Context: %wN and %wfN printf length modifier, new in C23. > gcc has supported the format, along with much of C23, since gcc 13, > and ARM's gcc-based toolchain version 13.2 is from October 2023. (The > current version is 15.2 from December 2025.) But I don't know about > library support - that is a very different matter. (Compiler support > for printf really just means checking the format specifiers match the > parameters.) Of course printf is implemented in the library, not in the compiler. gcc has had format checking for %wN and %wfN since release 13, but that's useless in the absence of library support. Support in glibc was added 2023-06-19 and released in version 2.39. Other C library implementations may or may not support it. [...] -- Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com void Void(void) { Void(); } /* The recursive call of the void */