diff --git a/libc/Android.mk b/libc/Android.mk index 262850718..f7e0e8ff1 100644 --- a/libc/Android.mk +++ b/libc/Android.mk @@ -346,6 +346,7 @@ libc_common_src_files += \ arch-arm/bionic/__get_sp.S \ arch-arm/bionic/_exit_with_stack_teardown.S \ arch-arm/bionic/_setjmp.S \ + arch-arm/bionic/abort_arm.S \ arch-arm/bionic/atomics_arm.S \ arch-arm/bionic/clone.S \ arch-arm/bionic/eabi.c \ diff --git a/libc/arch-arm/bionic/abort_arm.S b/libc/arch-arm/bionic/abort_arm.S new file mode 100644 index 000000000..51b0871fa --- /dev/null +++ b/libc/arch-arm/bionic/abort_arm.S @@ -0,0 +1,42 @@ +/* + * Copyright (C) 2012 The Android Open Source Project + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include + +/* + * Coding the abort function in assembly so that registers are guaranteed to + * be preserved properly regardless of GCC's assumption on the "noreturn" + * attribute. When the registers are not properly preserved we won't be able + * to unwind the stack all the way to the bottom to fully reveal the call + * sequence when the crash happens. + */ +ENTRY(abort) + .save {r3, r14} + stmfd sp!, {r3, r14} + blx PIC_SYM(_C_LABEL(__libc_android_abort), PLT) +END(abort) diff --git a/libc/unistd/abort.c b/libc/unistd/abort.c index 8b8659b8b..a3f8c5423 100644 --- a/libc/unistd/abort.c +++ b/libc/unistd/abort.c @@ -102,29 +102,3 @@ abort(void) (void)kill(getpid(), SIGABRT); _exit(1); } - -#ifdef __arm__ -/* - * abort() does not return, which gcc interprets to mean that it doesn't - * need to preserve any of the callee-save registers. Unfortunately this - * includes the link register, so if LR is used there is no way to determine - * which function called abort(). - * - * We work around this by inserting a trivial stub that doesn't alter - * any of the "interesting" registers and thus doesn't need to save them. - * We can't just call __libc_android_abort from C because gcc uses "bl" - * without first saving LR, so we use an asm statement. This also has - * the side-effect of replacing abort() with __libc_android_abort() in - * the stack trace. - * - * Ideally __libc_android_abort would be static, but I haven't figured out - * how to tell gcc to call a static function from an asm statement. - */ -void -abort(void) -{ - asm ("b __libc_android_abort"); - _exit(1); /* suppress gcc noreturn warnings */ -} -#endif -