zig

commit 988ddd1bed003f2c2e7436d5f245a06cb8d024ce (tree)
parent e5894221f7a886c8b0cc21b8369e4d3bf11890b0
Author: Isaac Freund <ifreund@ifreund.xyz>
Date:   Sat, 26 Dec 2020 22:22:43 +0100

std: add c._exit() and use in ChildProcess

This issue with atexit() functions after forking isn't isolated to linux
I'm sure, the proper way to do this when linking libc is to use _exit(2)

Diffstat:
M
lib/std/c.zig
 | 
1
+
M
lib/std/child_process.zig
 | 
5
+++--

2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/lib/std/c.zig b/lib/std/c.zig
@@ -81,6 +81,7 @@ pub extern "c" fn fread(ptr: [*]u8, size_of_type: usize, item_count: usize, stre
 pub extern "c" fn printf(format: [*:0]const u8, ...) c_int;
 pub extern "c" fn abort() noreturn;
 pub extern "c" fn exit(code: c_int) noreturn;
+pub extern "c" fn _exit(code: c_int) noreturn;
 pub extern "c" fn isatty(fd: fd_t) c_int;
 pub extern "c" fn close(fd: fd_t) c_int;
 pub extern "c" fn lseek(fd: fd_t, offset: off_t, whence: c_int) off_t;
diff --git a/lib/std/child_process.zig b/lib/std/child_process.zig
@@ -848,8 +848,9 @@ fn forkChildErrReport(fd: i32, err: ChildProcess.SpawnError) noreturn {
     // which we really do not want to run in the fork child. I caught LLVM doing this and
     // it caused a deadlock instead of doing an exit syscall. In the words of Avril Lavigne,
     // "Why'd you have to go and make things so complicated?"
-    if (std.Target.current.os.tag == .linux) {
-        std.os.linux.exit(1); // By-pass libc regardless of whether it is linked.
+    if (builtin.link_libc) {
+        // The _exit(2) function does nothing but make the exit syscall, unlike exit(3)
+        std.c._exit(1);
     }
     os.exit(1);
 }