From 4698c567a3f2a1e39319f0da7d7736deef70fecd Mon Sep 17 00:00:00 2001
From: Jinzhe Zeng <jinzhe.zeng@rutgers.edu>
Date: Sun, 22 Dec 2024 01:47:38 -0500
Subject: [PATCH] fix: print dlerror if dlopen fails (#4485)

xref: https://github.com/njzjz/deepmd-gnn/issues/44

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **New Features**
- Enhanced error messages for library loading failures on non-Windows
platforms.
- Updated thread management environment variable checks for improved
compatibility.
- Added support for mixed types in tensor input handling, allowing for
more flexible configurations.

- **Bug Fixes**
	- Improved error reporting for dynamic library loading issues.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
(cherry picked from commit cfe17a3e3e2fd198a42d9591d203bd2975c72824)
---
 source/api_cc/src/common.cc              | 8 +++++++-
 source/lib/src/gpu/cudart/cudart_stub.cc | 4 ++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/source/api_cc/src/common.cc b/source/api_cc/src/common.cc
index 5a4f05d75c..6d5ffcde48 100644
--- a/source/api_cc/src/common.cc
+++ b/source/api_cc/src/common.cc
@@ -389,7 +389,13 @@ static inline void _load_library_path(std::string dso_path) {
   if (!dso_handle) {
     throw deepmd::deepmd_exception(
         dso_path +
-        " is not found! You can add the library directory to LD_LIBRARY_PATH");
+        " is not found or fails to load! You can add the library directory to "
+        "LD_LIBRARY_PATH."
+#ifndef _WIN32
+        " Error message: " +
+        std::string(dlerror())
+#endif
+    );
   }
 }
 
diff --git a/source/lib/src/gpu/cudart/cudart_stub.cc b/source/lib/src/gpu/cudart/cudart_stub.cc
index 8083a0a89d..cfbabd6f5e 100644
--- a/source/lib/src/gpu/cudart/cudart_stub.cc
+++ b/source/lib/src/gpu/cudart/cudart_stub.cc
@@ -25,6 +25,10 @@ void *DP_cudart_dlopen(char *libname) {
 #endif
     if (!dso_handle) {
       std::cerr << "DeePMD-kit: Cannot find " << libname << std::endl;
+#ifndef _WIN32
+      std::cerr << "DeePMD-kit: Error message: " << std::string(dlerror())
+                << std::endl;
+#endif
       return nullptr;
     }
     std::cerr << "DeePMD-kit: Successfully load " << libname << std::endl;