Implement ARM GNU-style interrupt attribute

This attribute allows users to use a modified C or C++ function as an ARM
exception-handling function and, with care, to successfully return control to
user-space after the issue has been dealt with.

rdar://problem/14207019

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191769 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index 950c8df..c6337a5 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -289,7 +289,7 @@
 /// literal.
 bool Sema::checkStringLiteralArgumentAttr(const AttributeList &Attr,
                                           unsigned ArgNum, StringRef &Str,
-                                          SourceLocation *ArgLocation = 0) {
+                                          SourceLocation *ArgLocation) {
   // Look for identifiers. If we have one emit a hint to fix it to a literal.
   if (Attr.isArgIdent(ArgNum)) {
     IdentifierLoc *Loc = Attr.getArgAsIdent(ArgNum);