On Fri, 2020-08-14 at 17:24 -0700, Nick Desaulniers wrote: > LLVM implemented a recent "libcall optimization" that lowers calls to > `sprintf(dest, "%s", str)` where the return value is used to > `stpcpy(dest, str) - dest`. This generally avoids the machinery involved > in parsing format strings. [] > diff --git a/include/linux/string.h b/include/linux/string.h [] > @@ -31,6 +31,9 @@ size_t strlcpy(char *, const char *, size_t); > #ifndef __HAVE_ARCH_STRSCPY > ssize_t strscpy(char *, const char *, size_t); > #endif > +#ifndef __HAVE_ARCH_STPCPY > +extern char *stpcpy(char *__restrict, const char *__restrict__); Why use two different forms for __restrict and __restrict__? Any real reason to use __restrict__ at all? It's used nowhere else in the kernel. $ git grep -w -P '__restrict_{0,2}' scripts/genksyms/keywords.c: // According to rth, c99 defines "_Bool", __restrict", __restrict__", "restrict". KAO scripts/genksyms/keywords.c: { "__restrict__", RESTRICT_KEYW },