Re: [PATCH] tools: Use fputc() calls in some functions
Steven Rostedt <[email protected]> Thu, 23 Jul 2026 10:33:36 -0400
| Newsgroups | dev.linux.lists.acpica-devel,dev.linux.lists.mptcp,dev.linux.lists.virtualization,org.kernel.vger.bpf,org.kernel.vger.kernel-janitors,org.kernel.vger.kvm,org.kernel.vger.linux-acpi,org.kernel.vger.linux-gpio,org.kernel.vger.linux-kernel,org.kernel.vger.linux-kselftest,org.kernel.vger.linux-perf-users,org.kernel.vger.linux-pm,org.kernel.vger.linux-trace-kernel,org.kernel.vger.netdev,org.kernel.vger.platform-driver-x86,org.kvack.linux-mm,org.ozlabs.lists.linuxppc-dev |
|---|---|
| Message-ID | <[email protected]> |
On Thu, 23 Jul 2026 06:47:00 -0700 Andi Kleen <[email protected]> wrote: > > The source code was transformed by using the Coccinelle software. > > gcc already does this transformation automatically. Yep, I showed this in my talk[1] that looked at what printf("Hello World!") does. Doing an objdump of: #include <stdio.h> int main(void) { printf("Hello World!\n"); return 0; } has: 0000000000001139 <main>: 1139: 55 push %rbp 113a: 48 89 e5 mov %rsp,%rbp 113d: 48 8d 05 c0 0e 00 00 lea 0xec0(%rip),%rax # 2004 <_IO_stdin_used+0x4> 1144: 48 89 c7 mov %rax,%rdi 1147: e8 e4 fe ff ff call 1030 <puts@plt> <<<--- puts and not printf 114c: b8 00 00 00 00 mov $0x0,%eax 1151: 5d pop %rbp 1152: c3 ret -- Steve [1] https://www.youtube.com/watch?v=JRyrhsx-L5Y