update

[gramanas]

Duplicate of https://reviews.llvm.org/D47097

[probinson]

I take it this was accidental? If there are weaknesses in our documentation for how to use Phabricator, please let us know. I know it is not always straightforward (I had a number of issues when I tried to start using it).

[gramanas]

It was a mistake on my part with the arcanist tool. The documentation is fine, the only problems I encountered were due to my ignorance of how these systems work.

lib/CodeGen/CGDecl.cpp

if (Qualifiers::ObjCLifetime lt = qs.getObjCLifetime()) {
       }
 
       // Enter the cleanup scope.
       EmitAutoVarWithLifetime(*this, D, DeclPtr, lt);
     }
   }
 
   // Store the initial value into the alloca.
-  if (DoStore)
-    EmitStoreOfScalar(ArgVal, lv, /* isInitialization */ true);
+  if (DoStore) {
+   auto DL = ApplyDebugLocation::CreateArtificial(*this);
+  }
 
   setAddrOfLocalVar(&D, DeclPtr);
 
   // Emit debug info for param declaration.
   if (CGDebugInfo *DI = getDebugInfo()) {
     if (CGM.getCodeGenOpts().getDebugInfo() >=
         codegenoptions::LimitedDebugInfo) {
       DI->EmitDeclareOfArgVariable(&D, DeclPtr.getPointer(), ArgNo, Builder);

test/CodeGen/debug-info-preserve-scope.c

+// RUN: %clang_cc1 -debug-info-kind=limited -emit-llvm -o - %s | FileCheck %s
+
+static int a;
+
+// CHECK-LABEL: define void @f
+void f(int b) {
+  a = b;
+}
+
+// CHECK: store i32 %b, i32* %b.addr, align 4, !dbg ![[dbgLocForStore:[0-9]+]]
+
+// CHECK: ![[dbgLocForStore]] = !DILocation(line: 0