[cling] Emit const variables only once (#13614)

Otherwise they are emitted as internal and we get double-construction
and -destruction on the same memory address due to the way we promote
internal declarations in KeepLocalGVPass.

According to upstream tests, the de-duplication doesn't work on Windows
(yet), but I think this problem is severe enough to fix it on the other
platforms sooner rather than later.

Fixes #13429

interpreter/cling/test/CodeGeneration/const.C

@@ -0,0 +1,37 @@
+//------------------------------------------------------------------------------
+// CLING - the C++ LLVM-based InterpreterG :)
+//
+// This file is dual-licensed: you can choose to license it under the University
+// of Illinois Open Source License or the GNU Lesser General Public License. See
+// LICENSE.TXT for details.
+//------------------------------------------------------------------------------
+
+// RUN: cat %s |  %cling 2>&1 | FileCheck %s
+
+extern "C" int printf(const char*, ...);
+
+struct A {
+  int val;
+  A(int v) : val(v) {
+    printf("A(%d), this = %p\n", val, this);
+  }
+  ~A() {
+    printf("~A(%d), this = %p\n", val, this);
+  }
+  int getVal() const { return val; }
+};
+
+const A a(1);
+// CHECK: A(1), this = [[PTR:.+]]
+
+a.val
+// CHECK-NEXT: (const int) 1
+a.getVal()
+// CHECK-NEXT: (int) 1
+a.val
+// CHECK-NEXT: (const int) 1
+a.getVal()
+// CHECK-NEXT: (int) 1
+
+// CHECK-NEXT: ~A(1), this = [[PTR]]
+// CHECK-NOT: ~A

interpreter/llvm-project/clang/lib/AST/ASTContext.cpp

@@ -10831,6 +10831,15 @@ GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) const {
 
 static GVALinkage basicGVALinkageForVariable(const ASTContext &Context,
                                              const VarDecl *VD) {
+  // As an extension for interactive REPLs, make sure constant variables are
+  // only emitted once instead of LinkageComputer::getLVForNamespaceScopeDecl
+  // marking them as internal.
+  if (Context.getLangOpts().CPlusPlus &&
+      VD->getType().isConstQualified() &&
+      !VD->getType().isVolatileQualified() && !VD->isInline() &&
+      !isa<VarTemplateSpecializationDecl>(VD) && !VD->getDescribedVarTemplate())
+    return GVA_DiscardableODR;
+
   if (!VD->isExternallyVisible())
     return GVA_Internal;
 

interpreter/llvm-project/llvm-project.tag

@@ -1 +1 @@
-ROOT-llvm13-20230921-01
+ROOT-llvm13-20231003-01

interpreter/llvm-project/llvm/lib/ExecutionEngine/Orc/LLJIT.cpp

@@ -483,7 +483,7 @@ GlobalCtorDtorScraper::operator()(ThreadSafeModule TSM,
       Inits.push_back(std::make_pair(E.Func, E.Priority));
     llvm::sort(Inits, [](const std::pair<Function *, unsigned> &LHS,
                          const std::pair<Function *, unsigned> &RHS) {
-      return LHS.first < RHS.first;
+      return LHS.second < RHS.second;
     });
     auto *EntryBlock = BasicBlock::Create(Ctx, "entry", InitFunc);
     IRBuilder<> IB(EntryBlock);