Add directives to force stop unwinding.
On aarch64/x86/x86_64 add a macro that inserts a cfi directive that will
stop unwinding.
For arm, clang doesn't allow emitting .cantunwind, so add a comment and
leave it the same as it current is.
Add this macro to __libc_init and __start_thread.
Also, remove duplicate compilation of libc_init_static.cpp that already
includes the static library that includes that file.
Bug: 15469122
Test: Did unwinds using new unwinder tool (unwind) and debuggerd -b
Test: and verified new unwinder works on aarch64/x86/x86_64.
Test: Verified that it works on old unwinder for aarch64/x86, but
Test: x86_64 doesn't work properly, but as well as before.
Change-Id: I77302e8f6c7ba1549d98a4a164106ee82c9ecadc
diff --git a/libc/private/bionic_macros.h b/libc/private/bionic_macros.h
index 303218e..b1dfc7f 100644
--- a/libc/private/bionic_macros.h
+++ b/libc/private/bionic_macros.h
@@ -66,4 +66,17 @@
return reinterpret_cast<T*>(align_up(reinterpret_cast<uintptr_t>(p), align));
}
+#if defined(__arm__)
+// Do not emit anything for arm, clang does not allow emiting an arm unwind
+// directive.
+// #define BIONIC_STOP_UNWIND asm volatile(".cantunwind")
+#define BIONIC_STOP_UNWIND
+#elif defined(__aarch64__)
+#define BIONIC_STOP_UNWIND asm volatile(".cfi_undefined x30")
+#elif defined(__i386__)
+#define BIONIC_STOP_UNWIND asm volatile(".cfi_undefined \%eip")
+#elif defined(__x86_64__)
+#define BIONIC_STOP_UNWIND asm volatile(".cfi_undefined \%rip")
+#endif
+
#endif // _BIONIC_MACROS_H_