[Lldb-commits] [lldb] [lldb] Enable locate module callback for main executable in launch mode (PR #176266)

[via lldb-commits]

https://github.com/GeorgeHuyubo updated https://github.com/llvm/llvm-project/pull/176266

>From 6d9532e2a8285395a801cf51d124053704d7d80f Mon Sep 17 00:00:00 2001
From: George Hu <georgehuyubo at gmail.com>
Date: Thu, 15 Jan 2026 15:01:33 -0800
Subject: [PATCH] [lldb] Enable locate module callback for main executable in
 launch mode

---
 lldb/include/lldb/Core/ModuleSpec.h | 15 +++++++++++++++
 lldb/source/Core/ModuleList.cpp     | 30 ++++++++++++++++++-----------
 lldb/source/Target/TargetList.cpp   |  4 ++++
 3 files changed, 38 insertions(+), 11 deletions(-)

diff --git a/lldb/include/lldb/Core/ModuleSpec.h b/lldb/include/lldb/Core/ModuleSpec.h
index acbc85b48f02c..1ce857c9765cb 100644
--- a/lldb/include/lldb/Core/ModuleSpec.h
+++ b/lldb/include/lldb/Core/ModuleSpec.h
@@ -138,6 +138,17 @@ class ModuleSpec {
   /// the specified module.
   void SetTarget(std::shared_ptr<Target> target) { m_target_wp = target; }
 
+  lldb::PlatformSP GetPlatformSP() const { return m_platform_wp.lock(); }
+
+  /// Set the platform to be used when resolving a module.
+  ///
+  /// This is useful when a Target is not yet available (e.g., during target
+  /// creation) but a Platform is. The platform can be used to invoke locate
+  /// module callbacks and other platform-specific module resolution logic.
+  void SetPlatform(std::shared_ptr<Platform> platform) {
+    m_platform_wp = platform;
+  }
+
   void Clear() {
     m_file.Clear();
     m_platform_file.Clear();
@@ -150,6 +161,7 @@ class ModuleSpec {
     m_source_mappings.Clear(false);
     m_object_mod_time = llvm::sys::TimePoint<>();
     m_target_wp.reset();
+    m_platform_wp.reset();
   }
 
   explicit operator bool() const {
@@ -283,6 +295,9 @@ class ModuleSpec {
   /// debug info search paths, can be essential. The target's platform can also
   /// be used to locate or download the specified module.
   std::weak_ptr<Target> m_target_wp;
+  /// The platform used when resolving a module. This is useful when a Target
+  /// is not yet available (e.g., during target creation) but a Platform is.
+  std::weak_ptr<Platform> m_platform_wp;
   uint64_t m_object_offset = 0;
   uint64_t m_object_size = 0;
   llvm::sys::TimePoint<> m_object_mod_time;
diff --git a/lldb/source/Core/ModuleList.cpp b/lldb/source/Core/ModuleList.cpp
index be6ff723e0ffa..e6d8192ea4a55 100644
--- a/lldb/source/Core/ModuleList.cpp
+++ b/lldb/source/Core/ModuleList.cpp
@@ -1103,18 +1103,26 @@ ModuleList::GetSharedModule(const ModuleSpec &module_spec, ModuleSP &module_sp,
   if (module_sp)
     return error;
 
-  // Try target's platform locate module callback before second attempt.
+  // Try platform's locate module callback before second attempt.
+  // The platform can come from either the Target (if available) or directly
+  // from the ModuleSpec (useful when Target is not yet created, e.g., during
+  // target creation for launch mode).
   if (invoke_locate_callback) {
-    TargetSP target_sp = module_spec.GetTargetSP();
-    if (target_sp && target_sp->IsValid()) {
-      if (PlatformSP platform_sp = target_sp->GetPlatform()) {
-        FileSpec symbol_file_spec;
-        platform_sp->CallLocateModuleCallbackIfSet(
-            module_spec, module_sp, symbol_file_spec, did_create_ptr);
-        if (module_sp) {
-          // The callback found a module.
-          return error;
-        }
+    PlatformSP platform_sp;
+    if (TargetSP target_sp = module_spec.GetTargetSP()) {
+      if (target_sp->IsValid())
+        platform_sp = target_sp->GetPlatform();
+    }
+    if (!platform_sp)
+      platform_sp = module_spec.GetPlatformSP();
+
+    if (platform_sp) {
+      FileSpec symbol_file_spec;
+      platform_sp->CallLocateModuleCallbackIfSet(
+          module_spec, module_sp, symbol_file_spec, did_create_ptr);
+      if (module_sp) {
+        // The callback found a module.
+        return error;
       }
     }
   }
diff --git a/lldb/source/Target/TargetList.cpp b/lldb/source/Target/TargetList.cpp
index ce04e9c1209b8..623f8c4cf8324 100644
--- a/lldb/source/Target/TargetList.cpp
+++ b/lldb/source/Target/TargetList.cpp
@@ -306,6 +306,10 @@ Status TargetList::CreateTargetInternal(Debugger &debugger,
     if (platform_sp) {
       ModuleSpec module_spec(file, arch);
       module_spec.SetTarget(target_sp);
+      // Set the platform so that GetSharedModule can use it for the locate
+      // module callback, even when Target is not yet available (during target
+      // creation for launch mode).
+      module_spec.SetPlatform(platform_sp);
       error = platform_sp->ResolveExecutable(module_spec, exe_module_sp);
     }