diff options
Diffstat (limited to 'sysdeps/i386')
| -rw-r--r-- | sysdeps/i386/elf/start.S | 51 |
1 files changed, 13 insertions, 38 deletions
diff --git a/sysdeps/i386/elf/start.S b/sysdeps/i386/elf/start.S index e8ed2043ff..95f74ed647 100644 --- a/sysdeps/i386/elf/start.S +++ b/sysdeps/i386/elf/start.S @@ -43,57 +43,32 @@ _start: the outermost frame obviously. */ xorl %ebp, %ebp - /* %edx contains the address of the shared library termination - function, which we will register with `atexit' to be called by - `exit'. I suspect that on some systems, and when statically - linked, this will not be set by anything to any function - pointer; hopefully it will be zero so we don't try to call - random pointers. */ - testl %edx,%edx - jz .Lnofini - pushl %edx - call atexit - popl %eax /* Pop value to unused register to remove - argument from stack. */ -.Lnofini: - - /* Do essential libc initialization. In statically linked - programs under the GNU Hurd, this is what sets up the - arguments on the stack for the code below. */ - call __libc_init_first - - /* Extract the arguments and environment as encoded on the stack - and set up the arguments for `main': argc, argv, envp. */ + /* Extract the arguments as encoded on the stack and set up + the arguments for `main': argc, argv. envp will be determined + later in __libc_start_main. */ popl %esi /* Pop the argument count. */ - leal 4(%esp,%esi,4), %eax /* envp = &argv[argc + 1] */ - movl %eax, _environ /* Store it in the global variable. */ - movl %esp, %edx /* argv starts just at the current stack top.*/ + movl %esp, %ecx /* argv starts just at the current stack top.*/ /* Before pushing the arguments align the stack to a double word boundary to avoid penalties from misaligned accesses. Thanks to Edward Seidl <seidl@janed.com> for pointing this out. */ andl $0xfffffff8, %esp - pushl %eax /* Push garbage because we allocate - twelve more bytes. */ + pushl %edx /* Push address of the shared library + termination function. */ - pushl %eax /* Push third argument: envp. */ - pushl %edx /* Push second argument: argv. */ + /* Push address of our own entry points to .fini and .init. */ + pushl $_fini + pushl $_init + + pushl %ecx /* Push second argument: argv. */ pushl %esi /* Push first argument: argc. */ - /* Call `_init', which is the entry point to our own `.init' - section; and register with `atexit' to have `exit' call - `_fini', which is the entry point to our own `.fini' section. */ - call _init - pushl $_fini - call atexit - popl %eax + pushl $main /* Call the user's main function, and exit with its value. But let the libc call main. */ - movl $main, %eax - pushl %eax call __libc_start_main - call exit + hlt /* Crash if somehow `exit' does return. */ /* To fulfill the System V/i386 ABI we need this symbol. Yuck, it's so |