IR: Initialize DerefOrNullBytes in the AttrBuilder constructors

MSAN pointed out that this value is used uninitialized:

    http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/3678

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236686 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/IR/Attributes.h b/include/llvm/IR/Attributes.h
index 57573c4d49974ad20251328ff5953089677a7d19..24fae1847d83ab225016cd7c4833a1828a2b4b0c 100644 (file)
--- a/include/llvm/IR/Attributes.h
+++ b/include/llvm/IR/Attributes.h
@@ -436,13 +436,17 @@ class AttrBuilder {
   uint64_t DerefBytes;
   uint64_t DerefOrNullBytes;
 public:
-  AttrBuilder() : Attrs(0), Alignment(0), StackAlignment(0), DerefBytes(0) {}
+  AttrBuilder()
+      : Attrs(0), Alignment(0), StackAlignment(0), DerefBytes(0),
+        DerefOrNullBytes(0) {}
   explicit AttrBuilder(uint64_t Val)
-    : Attrs(0), Alignment(0), StackAlignment(0), DerefBytes(0) {
+      : Attrs(0), Alignment(0), StackAlignment(0), DerefBytes(0),
+        DerefOrNullBytes(0) {
     addRawValue(Val);
   }
   AttrBuilder(const Attribute &A)
-    : Attrs(0), Alignment(0), StackAlignment(0), DerefBytes(0) {
+      : Attrs(0), Alignment(0), StackAlignment(0), DerefBytes(0),
+        DerefOrNullBytes(0) {
     addAttribute(A);
   }
   AttrBuilder(AttributeSet AS, unsigned Idx);