[clang] f8dadef - [CodeGen] Keep track of eagerly emitted globals

[Jonas Hahnfeld via cfe-commits]

Author: Jonas Hahnfeld
Date: 2023-08-17T13:26:22+02:00
New Revision: f8dadefd4afc8e1b7b9a1e69a0ba8df051e03328

URL: https://github.com/llvm/llvm-project/commit/f8dadefd4afc8e1b7b9a1e69a0ba8df051e03328
DIFF: https://github.com/llvm/llvm-project/commit/f8dadefd4afc8e1b7b9a1e69a0ba8df051e03328.diff

LOG: [CodeGen] Keep track of eagerly emitted globals

An inline virtual function must be emitted, but we need to remember
it and emit the same definition again in the future in case later
LLVM optimizations stripped it from the Module. The added test case
shows the problem; before this patch, it would fail with:
    Symbols not found: [ _ZN1AD0Ev, _ZN1AD1Ev ]

Differential Revision: https://reviews.llvm.org/D156537

Added: 
    clang/test/Interpreter/inline-virtual.cpp

Modified: 
    clang/lib/CodeGen/CodeGenModule.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 517af514d9c998..440fb040a43cc5 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -3658,6 +3658,7 @@ void CodeGenModule::EmitGlobal(GlobalDecl GD) {
   if (MustBeEmitted(Global) && MayBeEmittedEagerly(Global)) {
     // Emit the definition if it can't be deferred.
     EmitGlobalDefinition(GD);
+    addEmittedDeferredDecl(GD);
     return;
   }
 

diff  --git a/clang/test/Interpreter/inline-virtual.cpp b/clang/test/Interpreter/inline-virtual.cpp
new file mode 100644
index 00000000000000..ace7a0a73d82a1
--- /dev/null
+++ b/clang/test/Interpreter/inline-virtual.cpp
@@ -0,0 +1,21 @@
+// REQUIRES: host-supports-jit
+// UNSUPPORTED: system-aix
+// RUN: cat %s | clang-repl | FileCheck %s
+// RUN: cat %s | clang-repl -Xcc -O2 | FileCheck %s
+
+extern "C" int printf(const char *, ...);
+
+struct A { int a; A(int a) : a(a) {} virtual ~A(); };
+
+// Then define the virtual destructor as inline out-of-line, in a separate
+// PartialTranslationUnit.
+inline A::~A() { printf("~A(%d)\n", a); }
+
+// Create one instance with new and delete it.
+A *a1 = new A(1);
+delete a1;
+// CHECK: ~A(1)
+
+// Also create one global that will be auto-destructed.
+A a2(2);
+// CHECK: ~A(2)