[PATCH] Segfault in AArch64 backend with -g and -mbig-endian

[Oliver Stannard]

================
Comment at: lib/Target/AArch64/MCTargetDesc/AArch64AsmBackend.cpp:538
@@ -537,3 +537,3 @@
     const MCSection *Sec = Fixup.getValue()->FindAssociatedSection();
-    const MCSectionELF *SecELF = static_cast<const MCSectionELF *>(Sec);
-    if (SecELF->getSectionName() == ".eh_frame")
+    const MCSectionELF *SecELF = dyn_cast_or_null<const MCSectionELF>(Sec);
+    if (SecELF && SecELF->getSectionName() == ".eh_frame")
----------------
Eric Christopher wrote:
> Fixup to a null section? How's that happen?
This is the section associated with the value to put into the fixup location, not the section containing the fixup location. This can be null if:
 * It is a symbol which is not defined by this translation unit
 * It is the difference between two temporary symbols, for example to find the length of a debug data structure.

http://reviews.llvm.org/D4870