Fix undefined symbol issue for transformer_engine::getenv (#763)

Signed-off-by: Jinze Xue <jinzex@nvidia.com>
Co-authored-by: Jinze Xue <jinzex@nvidia.com>

setup.py

@@ -445,6 +445,12 @@ def setup_pytorch_extension() -> setuptools.Extension:
     sources = [
         src_dir / "common.cu",
         src_dir / "ts_fp8_op.cpp",
+        # We need to compile system.cpp because the pytorch extension uses
+        # transformer_engine::getenv. This is a workaround to avoid direct
+        # linking with libtransformer_engine.so, as the pre-built PyTorch
+        # wheel from conda or PyPI was not built with CXX11_ABI, and will
+        # cause undefined symbol issues.
+        root_path / "transformer_engine" / "common" / "util" / "system.cpp",
     ] + \
     _all_files_in_dir(extensions_dir)