Le mar. 30 avr. 2024 à 15:01, Sam James <sam@xxxxxxxxxx> a écrit : > > Paul Eggert <eggert@xxxxxxxxxxx> writes: > > > On 2024-04-26 08:10, Zack Weinberg wrote: > > > >> I think what we should do here is fold AC_C_VARARRAYS into AC_PROG_CC. > >> Take the test for VLAs completely out of _AC_C_C99_TEST_MAIN, but > >> unconditionally *run* a test for VLAs as part of AC_PROG_CC. If that > >> test fails, and __STDC_NO_VLA__ was not defined by the compiler, > >> then AC_DEFINE([__STDC_NO_VLA__], 1) > > > > Although the basic strategy sounds reasonable, AC_PROG_CC is > > documented to operate by setting compiler options not via AC_DEFINE, > > so presumably this should put -D__STDC_NO_VLA__ into $CC rather than > > use AC_DEFINE. > > > > I installed the attached patch, which is less ambitious but should > > address the original problem report. The attached patch doesn't > > preclude your suggestion, which can be done later as needed. > > > > [2. text/x-patch; 0001-Port-better-to-MSVC.patch]... > > Note that "or later" isn't right -- C23 makes VLAs mandatory again. I don't think that's true… Wikipedia links to the paper modifying the standard: > For these reasons, we propose to make variably-modified types > mandatory in C23. VLAs with automatic storage duration remain an > optional language feature due to their higher implementation > overhead and security concerns on some implementations (i.e. when > allocated on the stack and not using stack probing). https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2778.pdf Best regards, Antonin
