[llvm] [ORC] Handle unset FinalizeFuture in ELFDebugObjectPlugin::awaitTargetMem (PR #175143)

[Anthonin Bonnefoy via llvm-commits]

https://github.com/bonnefoa created https://github.com/llvm/llvm-project/pull/175143

When debug registration is skipped, DebugObj->collectTargetAlloc() is never called, leaving the FinalizeFuture unset. The next call to awaitTargetMem will fail with a

```
terminate called after throwing an instance of 'std::future_error'
  what():  std::future_error: No associated state
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace and instructions to reproduce the bug.

PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace and instructions to reproduce the bug.
...
#13 0x0000ef6fd6ca2b50 void std::__future_base::_State_baseV2::_S_check<std::__future_base::_State_baseV2>(std::shared_ptr<std::__future_base::_State_baseV2> const&) /usr/lib/gcc/aarch64-linux-gnu/13/../../../../include/c++/13/future:582:9
#14 0x0000ef6fd6ca6574 std::__basic_future<llvm::MSVCPExpected<llvm::orc::ExecutorAddrRange>>::_M_get_result() const /usr/lib/gcc/aarch64-linux-gnu/13/../../../../include/c++/13/future:740:9
#15 0x0000ef6fd6ca628c std::future<llvm::MSVCPExpected<llvm::orc::ExecutorAddrRange>>::get() /usr/lib/gcc/aarch64-linux-gnu/13/../../../../include/c++/13/future:827:48
#16 0x0000ef6fd6cb4a40 llvm::orc::DebugObject::awaitTargetMem() /var/lib/postgresql/llvm-project/llvm/lib/ExecutionEngine/Orc/Debugging/ELFDebugObjectPlugin.cpp:78:72
#17 0x0000ef6fd6c9b3c8 llvm::orc::ELFDebugObjectPlugin::modifyPassConfig(llvm::orc::MaterializationResponsibility&, llvm::jitlink::LinkGraph&, llvm::jitlink::PassConfiguration&)::$_1::operator()(llvm::jitlink::LinkGraph&) const /var/lib/postgresql/llvm-project/llvm/lib/ExecutionEngine/Orc/Debugging/ELFDebugObjectPlugin.cpp:345:47
```

This patch modifies awaitTargetMem to return an empty address range if the FinalizeFuture is never initialised.

>From 040f99ea1083d98f8d9631307087d0ae14f07873 Mon Sep 17 00:00:00 2001
From: Anthonin Bonnefoy <anthonin.bonnefoy at datadoghq.com>
Date: Fri, 9 Jan 2026 09:53:10 +0100
Subject: [PATCH] [ORC] Handle unset FinalizeFuture in
 ELFDebugObjectPlugin::awaitTargetMem

When debug registration is skipped, DebugObj->collectTargetAlloc() is
never called, leaving the FinalizeFuture unset. The next call to
awaitTargetMem will fail with a "std::future_error: No associated state"

This patch modifies awaitTargetMem to return an empty address range if
the FinalizeFuture is never initialised.
---
 .../ExecutionEngine/Orc/Debugging/ELFDebugObjectPlugin.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/ExecutionEngine/Orc/Debugging/ELFDebugObjectPlugin.cpp b/llvm/lib/ExecutionEngine/Orc/Debugging/ELFDebugObjectPlugin.cpp
index e67eb323c3540..ac279e3ca6fb0 100644
--- a/llvm/lib/ExecutionEngine/Orc/Debugging/ELFDebugObjectPlugin.cpp
+++ b/llvm/lib/ExecutionEngine/Orc/Debugging/ELFDebugObjectPlugin.cpp
@@ -75,7 +75,12 @@ class DebugObject {
 
   void trackFinalizedAlloc(FinalizedAlloc FA) { Alloc = std::move(FA); }
 
-  Expected<ExecutorAddrRange> awaitTargetMem() { return FinalizeFuture.get(); }
+  Expected<ExecutorAddrRange> awaitTargetMem() {
+    if (!FinalizeFuture.valid()) {
+      return ExecutorAddrRange();
+    }
+    return FinalizeFuture.get();
+  }
 
   void reportTargetMem(ExecutorAddrRange TargetMem) {
     FinalizePromise.set_value(TargetMem);