Teach scanf/printf checking about '%Ld' and friends (a GNU extension).  Fixes PR 9466.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@148859 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScanfFormatString.cpp b/lib/Analysis/ScanfFormatString.cpp
index 38afd61..c1cdef8 100644
--- a/lib/Analysis/ScanfFormatString.cpp
+++ b/lib/Analysis/ScanfFormatString.cpp
@@ -218,7 +218,9 @@
           return ScanfArgTypeResult();
         case LengthModifier::AsPtrDiff:
           return ScanfArgTypeResult(Ctx.getPointerDiffType(), "ptrdiff_t *");
-        case LengthModifier::AsLongDouble: return ScanfArgTypeResult::Invalid();
+        case LengthModifier::AsLongDouble:
+          // GNU extension.
+          return ArgTypeResult(Ctx.LongLongTy);
         case LengthModifier::AsAllocate: return ScanfArgTypeResult::Invalid();
         case LengthModifier::AsMAllocate: return ScanfArgTypeResult::Invalid();
       }
@@ -242,7 +244,9 @@
         case LengthModifier::AsPtrDiff:
           // FIXME: Unsigned version of ptrdiff_t?
           return ScanfArgTypeResult();
-        case LengthModifier::AsLongDouble: return ScanfArgTypeResult::Invalid();
+        case LengthModifier::AsLongDouble:
+          // GNU extension.
+          return ArgTypeResult(Ctx.UnsignedLongLongTy);
         case LengthModifier::AsAllocate: return ScanfArgTypeResult::Invalid();
         case LengthModifier::AsMAllocate: return ScanfArgTypeResult::Invalid();
       }