From: Ben Wolsieffer <Ben.Wolsieffer(a)hefring.com>
fork() can be implemented using either the fork or clone syscalls on MMU
systems. Therefore the stub is only generated if neither __NR_fork nor
__NR_clone are defined. The stub code manually undefines __NR_fork on
no-MMU systems in an attempt to enable the stub, but this doesn't work
because __NR_clone is still defined. It is not appropriate to undefine
__NR_clone because clone is available on no-MMU, it is just not capable
of implementing fork.
This patch directly enables the fork stub if __ARCH_USE_MMU__ is not
defined. This eliminates the need to undefine __NR_fork, so this code is
removed
Signed-off-by: Ben Wolsieffer <ben.wolsieffer(a)hefring.com>
---
libc/sysdeps/linux/common/stubs.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/libc/sysdeps/linux/common/stubs.c b/libc/sysdeps/linux/common/stubs.c
index c17e509b9..634dcde0d 100644
--- a/libc/sysdeps/linux/common/stubs.c
+++ b/libc/sysdeps/linux/common/stubs.c
@@ -34,10 +34,6 @@ __attribute_used__ static int ret_enosys_stub(void)
link_warning(stub, #stub ": this function is not implemented") \
strong_alias(ret_enosys_stub, stub)
-#ifndef __ARCH_USE_MMU__
-# undef __NR_fork
-#endif
-
#ifdef __arm__
# define __NR_fadvise64_64 __NR_arm_fadvise64_64
# define __NR_fadvise64 __NR_arm_fadvise64_64
@@ -120,7 +116,7 @@ make_stub(fgetxattr)
make_stub(flistxattr)
#endif
-#if !defined __NR_fork && !defined __NR_clone
+#if !defined __ARCH_USE_MMU__ || (!defined __NR_fork && !defined __NR_clone)
make_stub(fork)
#endif
--
2.42.0