glibc/include/setjmp.h
Samuel Thibault 3d3316b1de hurd: keep only required PLTs in ld.so
We need NO_RTLD_HIDDEN because of the need for PLT calls in ld.so.
See Roland's comment in
https://sourceware.org/bugzilla/show_bug.cgi?id=15605
"in the Hurd it's crucial that calls like __mmap be the libc ones
instead of the rtld-local ones after the bootstrap phase, when the
dynamic linker is being used for dlopen and the like."

We used to just avoid all hidden use in the rtld ; this commit switches to
keeping only those that should use PLT calls, i.e. essentially those defined in
sysdeps/mach/hurd/dl-sysdep.c:

__assert_fail
__assert_perror_fail
__*stat64
_exit

This fixes a few startup issues, notably the call to __tunable_get_val that is
made before PLTs are set up.
2020-11-11 02:36:22 +01:00

70 lines
2.1 KiB
C

#ifndef _SETJMP_H
#include <setjmp/setjmp.h>
#ifndef _ISOMAC
/* Now define the internal interfaces. */
/* Internal machine-dependent function to restore context sans signal mask. */
extern void __longjmp (__jmp_buf __env, int __val)
__attribute__ ((__noreturn__)) attribute_hidden;
extern void ____longjmp_chk (__jmp_buf __env, int __val)
__attribute__ ((__noreturn__)) attribute_hidden;
/* Internal function to possibly save the current mask of blocked signals
in ENV, and always set the flag saying whether or not it was saved.
This is used by the machine-dependent definition of `__sigsetjmp'.
Always returns zero, for convenience. */
extern int __sigjmp_save (jmp_buf __env, int __savemask);
extern void _longjmp_unwind (jmp_buf env, int val);
extern void __libc_siglongjmp (sigjmp_buf env, int val)
__attribute__ ((noreturn));
extern void __libc_longjmp (sigjmp_buf env, int val)
__attribute__ ((noreturn));
libc_hidden_proto (_setjmp)
libc_hidden_proto (__sigsetjmp)
# if IS_IN (rtld)
extern __typeof (__sigsetjmp) __sigsetjmp attribute_hidden;
# endif
/* Check jmp_buf sizes, alignments and offsets. */
# include <stddef.h>
# include <jmp_buf-macros.h>
# define SJSTR_HELPER(x) #x
# define SJSTR(x) SJSTR_HELPER(x)
# define TEST_SIZE(type, size) \
_Static_assert (sizeof (type) == size, \
"size of " #type " != " \
SJSTR (size))
# define TEST_ALIGN(type, align) \
_Static_assert (__alignof__ (type) == align , \
"align of " #type " != " \
SJSTR (align))
# define TEST_OFFSET(type, member, offset) \
_Static_assert (offsetof (type, member) == offset, \
"offset of " #member " field of " #type " != " \
SJSTR (offset))
/* Check if jmp_buf have the expected sizes. */
TEST_SIZE (jmp_buf, JMP_BUF_SIZE);
TEST_SIZE (sigjmp_buf, SIGJMP_BUF_SIZE);
/* Check if jmp_buf have the expected alignments. */
TEST_ALIGN (jmp_buf, JMP_BUF_ALIGN);
TEST_ALIGN (sigjmp_buf, SIGJMP_BUF_ALIGN);
/* Check if internal fields in jmp_buf have the expected offsets. */
TEST_OFFSET (struct __jmp_buf_tag, __mask_was_saved,
MASK_WAS_SAVED_OFFSET);
TEST_OFFSET (struct __jmp_buf_tag, __saved_mask,
SAVED_MASK_OFFSET);
#endif
#endif