Add subinterpreter support

Dockerfile

@@ -53,6 +53,7 @@ RUN apt-get update \
     file \
     less \
     libcrypt-dev \
+    bear \
     libzstd-dev \
     liblzma-dev \
     libbz2-dev \

news/279.feature.rst

@@ -0,0 +1 @@
+Add support for Python subinterpreters. When a process uses multiple interpreters (e.g. via Python 3.14's ``concurrent.interpreters`` module), stacks for all interpreters are now reported instead of just the main one.

src/pystack/__init__.py

@@ -1,7 +1,7 @@
 from ._version import __version__
-from .traceback_formatter import print_thread
+from .traceback_formatter import print_threads
 
 __all__ = [
     "__version__",
-    "print_thread",
+    "print_threads",
 ]

src/pystack/__main__.py

@@ -19,7 +19,7 @@
 from pystack.process import is_gzip
 
 from . import errors
-from . import print_thread
+from . import print_threads
 from .colors import colored
 from .engine import CoreFileAnalyzer
 from .engine import NativeReportingMode
@@ -287,14 +287,14 @@ def process_remote(parser: argparse.ArgumentParser, args: argparse.Namespace) ->
     if not args.block and args.native_mode != NativeReportingMode.OFF:
         parser.error("Native traces are only available in blocking mode")
 
-    for thread in get_process_threads(
+    threads = get_process_threads(
         args.pid,
         stop_process=args.block,
         native_mode=args.native_mode,
         locals=args.locals,
         method=StackMethod.ALL if args.exhaustive else StackMethod.AUTO,
-    ):
-        print_thread(thread, args.native_mode)
+    )
+    print_threads(threads, args.native_mode)
 
 
 def format_psinfo_information(psinfo: Dict[str, Any]) -> str:
@@ -414,15 +414,15 @@ def process_core(parser: argparse.ArgumentParser, args: argparse.Namespace) -> N
                 elf_id if elf_id else "<MISSING>",
             )
 
-    for thread in get_process_threads_for_core(
+    threads = get_process_threads_for_core(
         corefile,
         executable,
         library_search_path=lib_search_path,
         native_mode=args.native_mode,
         locals=args.locals,
         method=StackMethod.ALL if args.exhaustive else StackMethod.AUTO,
-    ):
-        print_thread(thread, args.native_mode)
+    )
+    print_threads(threads, args.native_mode)
 
 
 if __name__ == "__main__":  # pragma: no cover

src/pystack/_pystack.pyi

@@ -84,6 +84,11 @@ def get_process_threads_for_core(
 def get_bss_info(binary: Union[str, pathlib.Path]) -> Optional[Dict[str, Any]]: ...
 def copy_memory_from_address(pid: int, address: int, size: int) -> bytes: ...
 def _check_interpreter_shutdown(manager: ProcessManager) -> None: ...
+def is_eval_frame(symbol: str, python_version: Tuple[int, int]) -> bool: ...
+def _normalize_threads_for_testing(
+    thread_descs: List[Dict[str, Any]],
+    native_mode: NativeReportingMode,
+) -> List[PyThread]: ...
 
 F = TypeVar("F", bound=Callable[..., Any])
 

src/pystack/_pystack/CMakeLists.txt

@@ -11,6 +11,7 @@ set(PYSTACK_SOURCES
     logging.cpp
     maps_parser.cpp
     mem.cpp
+    native_frame.cpp
     process.cpp
     pycode.cpp
     pyframe.cpp
@@ -21,6 +22,7 @@ set(PYSTACK_SOURCES
     version.cpp
     version_detector.cpp
     bindings.cpp
+    interpreter.cpp
 )
 
 # Create the nanobind module