[Sema] Don't create an invalid source range for overlong initializer lists.

We took both source locations from the end of the initializer list what
the code below doesn't expect. This can lead to a crash when rendering
the diagnostic (PR24816). Assert that we have more than one element in
a scalar initializer with too many elements.

llvm-svn: 248391

2 files changed, 8 insertions, 2 deletions

diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp
index de11666747a..74db24f28dc 100644
--- a/clang/lib/Sema/SemaInit.cpp
+++ b/clang/lib/Sema/SemaInit.cpp
@@ -7047,10 +7047,12 @@ bool InitializationSequence::Diagnose(Sema &S,
     SourceRange R;
 
     auto *InitList = dyn_cast<InitListExpr>(Args[0]);
-    if (InitList && InitList->getNumInits() == 1)
+    if (InitList && InitList->getNumInits() >= 1) {
       R = SourceRange(InitList->getInit(0)->getLocEnd(), InitList->getLocEnd());
-    else
+    } else {
+      assert(Args.size() > 1 && "Expected multiple initializers!");
       R = SourceRange(Args.front()->getLocEnd(), Args.back()->getLocEnd());
+    }
 
     R.setBegin(S.getLocForEndOfToken(R.getBegin()));
     if (Kind.isCStyleOrFunctionalCast())
diff --git a/clang/test/SemaCXX/cxx0x-initializer-aggregates.cpp b/clang/test/SemaCXX/cxx0x-initializer-aggregates.cpp
index 0e9a97d5bb0..1b01a351f78 100644
--- a/clang/test/SemaCXX/cxx0x-initializer-aggregates.cpp
+++ b/clang/test/SemaCXX/cxx0x-initializer-aggregates.cpp
@@ -129,3 +129,7 @@ namespace array_addressof {
   using T = int[5];
   T *p = &T{1,2,3,4,5}; // expected-error {{taking the address of a temporary object of type 'T' (aka 'int [5]')}}
 }
+
+namespace PR24816 {
+  struct { int i; } ne = {{0, 1}}; // expected-error{{excess elements in scalar initializer}}
+}