fix _dyld_find_unwind_sections() for pre-10.7. Patch by Jeremy Sequoia
git-svn-id: https://llvm.org/svn/llvm-project/libunwind/trunk@285636 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/src/AddressSpace.hpp b/src/AddressSpace.hpp
index 2792e0e..67aa664 100644
--- a/src/AddressSpace.hpp
+++ b/src/AddressSpace.hpp
@@ -321,28 +321,34 @@
// In 10.7.0 or later, libSystem.dylib implements this function.
extern "C" bool _dyld_find_unwind_sections(void *, dyld_unwind_sections *);
#else
- // In 10.6.x and earlier, we need to implement this functionality.
+ // In 10.6.x and earlier, we need to implement this functionality. Note
+ // that this requires a newer version of libmacho (from cctools) than is
+ // present in libSystem on 10.6.x (for getsectiondata).
static inline bool _dyld_find_unwind_sections(void* addr,
dyld_unwind_sections* info) {
// Find mach-o image containing address.
Dl_info dlinfo;
if (!dladdr(addr, &dlinfo))
return false;
- const mach_header *mh = (const mach_header *)dlinfo.dli_saddr;
-
- // Find DWARF unwind section in that image.
- unsigned long size;
- const uint8_t *p = getsectiondata(mh, "__TEXT", "__eh_frame", &size);
- if (!p)
- return false;
-
- // Fill in return struct.
- info->mh = mh;
- info->dwarf_section = p;
- info->dwarf_section_length = size;
- info->compact_unwind_section = 0;
- info->compact_unwind_section_length = 0;
-
+#if __LP64__
+ const struct mach_header_64 *mh = (const struct mach_header_64 *)dlinfo.dli_fbase;
+#else
+ const struct mach_header *mh = (const struct mach_header *)dlinfo.dli_fbase;
+#endif
+
+ // Initialize the return struct
+ info->mh = (const struct mach_header *)mh;
+ info->dwarf_section = getsectiondata(mh, "__TEXT", "__eh_frame", &info->dwarf_section_length);
+ info->compact_unwind_section = getsectiondata(mh, "__TEXT", "__unwind_info", &info->compact_unwind_section_length);
+
+ if (!info->dwarf_section) {
+ info->dwarf_section_length = 0;
+ }
+
+ if (!info->compact_unwind_section) {
+ info->compact_unwind_section_length = 0;
+ }
+
return true;
}
#endif
