Le jeu. 13 mai 2021 à 21:44, Joerg Sonnenberger <jo...@bec.de> a écrit : > > No we don't, unless you are using PCC :D > > > > The block in <stdlib.h> only provides an alloca(3) prototype, and only > > if the compiler already #defines alloca as __builtin_alloca. > > > > While this works for gcc in some -std modes (e.g. gnu++14), it does > > not in others (c++14, c++11). > > Your analysis is wrong. We don't provide a prototype in standard modes > as that violates the user request. The prototype is enough to trigger > the builtin logic in GCC and Clang.
Allright. Anyway, would it be wrong to add <alloca.h> which unconditionally makes alloca() use the builtin, similar to what e.g. glibc (Linux) and FreeBSD do, or is it fundamentally wrong doing so? Jaromir
