cuda.core: emit -numba-debug to libNVVM, not --numba-debug

libNVVM accepts only single-dashed options, so every
ProgramOptions(numba_debug=True) compile on the NVVM backend failed with
NVVM_ERROR_INVALID_OPTION. numba-cuda emits -numba-debug for the same
path. The NVRTC backend tolerates both spellings and is left alone.

The guarding test probed libNVVM with the same wrong spelling, so it
skipped on every configuration and never caught this. Probe and assert
the spelling the code now emits, and drop the skip reason's claim that
the option needs CTK 13.2: libNVVM rejects the double-dashed form at any
version.

Closes #2570

Signed-off-by: Vyron Vasileiadis <hi@fedonman.com>

Author: fedonman

cuda_core/cuda/core/_program.pyx

@@ -1233,7 +1233,7 @@ cdef inline object _prepare_nvvm_options_impl(object opts, bint as_bytes):
     if opts.debug is not None and opts.debug:
         options.append("-g")
     if opts.numba_debug:
-        options.append("--numba-debug")
+        options.append("-numba-debug")
     if opts.device_code_optimize is False:
         options.append("-opt=0")
     elif opts.device_code_optimize is True:

cuda_core/docs/source/release/1.2.0-notes.rst

@@ -73,6 +73,13 @@ Fixes and enhancements
   Windows, both ``ctypes.CFUNCTYPE`` and ``ctypes.WINFUNCTYPE`` are accepted.
   (`#2439 <https://github.com/NVIDIA/cuda-python/issues/2439>`__)
 
+- ``ProgramOptions(numba_debug=True)`` now works on the NVVM backend. The
+  option was emitted as ``--numba-debug``, and libNVVM accepts only the
+  single-dashed ``-numba-debug``, so every such compilation failed with
+  ``NVVM_ERROR_INVALID_OPTION``. The NVRTC backend, which tolerates both
+  spellings, was unaffected.
+  (`#2570 <https://github.com/NVIDIA/cuda-python/issues/2570>`__)
+
 Deprecation Notices
 -------------------
 

cuda_core/tests/test_program.py

@@ -93,12 +93,12 @@ def _check_nvvm_arch(arch: str) -> bool:
 
 
 def _check_nvvm_supports_numba_debug() -> bool:
-    """Check if the installed libNVVM recognizes --numba-debug (CTK 13.2+)."""
+    """Check if the installed libNVVM recognizes -numba-debug."""
     if not _has_check_nvvm_compiler_options():
         return False
     from cuda.bindings.utils import check_nvvm_compiler_options
 
-    return check_nvvm_compiler_options(["--numba-debug"])
+    return check_nvvm_compiler_options(["-numba-debug"])
 
 
 @pytest.fixture(scope="session")
@@ -762,18 +762,19 @@ def test_program_options_as_bytes_nvvm_unsupported_option():
 
 @nvvm_available
 def test_nvvm_program_options_as_bytes_numba_debug():
-    """numba_debug must be plumbed through to libNVVM as --numba-debug
-    (see #1287)."""
+    """numba_debug must be plumbed through to libNVVM as -numba-debug
+    (see #1287). libNVVM rejects the double-dashed form of every option."""
     options = ProgramOptions(arch="sm_80", debug=True, numba_debug=True)
     nvvm_bytes = options.as_bytes("nvvm")
-    assert b"--numba-debug" in nvvm_bytes
+    assert b"-numba-debug" in nvvm_bytes
+    assert b"--numba-debug" not in nvvm_bytes
     assert b"-g" in nvvm_bytes
 
 
 @nvvm_available
 @pytest.mark.skipif(
     not _check_nvvm_supports_numba_debug(),
-    reason="installed libNVVM does not recognize --numba-debug (needs CTK 13.2+)",
+    reason="installed libNVVM does not recognize -numba-debug",
 )
 def test_nvvm_program_numba_debug(init_cuda, nvvm_ir):
     options = ProgramOptions(arch="sm_80", debug=True, numba_debug=True)