AIX: add collector/python CGO flags and rtloader changes

pkg/collector/python/containers.go

@@ -14,7 +14,8 @@ import (
 
 /*
 #include <datadog_agent_rtloader.h>
-#cgo !windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo !aix,!windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo aix LDFLAGS: -ldl
 #cgo windows LDFLAGS: -ldatadog-agent-rtloader -lstdc++ -static
 */
 import "C"

pkg/collector/python/datadog_agent.go

@@ -31,7 +31,8 @@ import (
 )
 
 /*
-#cgo !windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo !aix,!windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo aix LDFLAGS: -ldl
 #cgo windows LDFLAGS: -ldatadog-agent-rtloader -lstdc++ -static
 
 #include "datadog_agent_rtloader.h"

pkg/collector/python/init.go

@@ -34,7 +34,10 @@ import (
 )
 
 /*
-#cgo !windows LDFLAGS: -L${SRCDIR}/../../../rtloader/build/rtloader -ldatadog-agent-rtloader -ldl
+// On AIX, Go's CGO requires shared libraries to be wrapped in .a archives.
+// libdatadog-agent-rtloader.a is built from the .so file using "ar -X64 -r".
+#cgo aix LDFLAGS: -L${SRCDIR}/../../../rtloader/build/rtloader -ldatadog-agent-rtloader -ldl
+#cgo !aix,!windows LDFLAGS: -L${SRCDIR}/../../../rtloader/build/rtloader -ldatadog-agent-rtloader -ldl
 #cgo windows LDFLAGS: -L${SRCDIR}/../../../rtloader/build/rtloader -ldatadog-agent-rtloader -lstdc++ -static
 #cgo CFLAGS: -I "${SRCDIR}/../../../rtloader/include"  -I "${SRCDIR}/../../../rtloader/common"
 

pkg/collector/python/init_nix.go

@@ -16,7 +16,8 @@ import (
 )
 
 /*
-#cgo !windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo !aix,!windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo aix LDFLAGS: -ldl
 
 #include <datadog_agent_rtloader.h>
 #include <rtloader_mem.h>

pkg/collector/python/kubeutil.go

@@ -20,7 +20,8 @@ import (
 
 /*
 #include <datadog_agent_rtloader.h>
-#cgo !windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo !aix,!windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo aix LDFLAGS: -ldl
 #cgo windows LDFLAGS: -ldatadog-agent-rtloader -lstdc++ -static
 */
 import "C"

pkg/collector/python/memory.go

@@ -18,7 +18,8 @@ import (
 )
 
 /*
-#cgo !windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo !aix,!windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo aix LDFLAGS: -ldl
 #cgo windows LDFLAGS: -ldatadog-agent-rtloader -lstdc++ -static
 
 #if defined(__linux__) || defined(_WIN32)

pkg/collector/python/no_kubeutil.go

@@ -9,7 +9,8 @@ package python
 
 /*
 #include <datadog_agent_rtloader.h>
-#cgo !windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo !aix,!windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo aix LDFLAGS: -ldl
 #cgo windows LDFLAGS: -ldatadog-agent-rtloader -lstdc++ -static
 */
 import "C"

pkg/collector/python/python_aix.go

@@ -0,0 +1,73 @@
+// Unless explicitly stated otherwise all files in this repository are licensed
+// under the Apache License Version 2.0.
+// This product includes software developed at Datadog (https://www.datadoghq.com/).
+// Copyright 2016-present Datadog, Inc.
+
+//go:build aix && python
+
+package python
+
+// Force libpython.so into the agent binary's XCOFF startup-load chain.
+//
+// Background
+// ----------
+// Python C extension modules (lib-dynload/_decimal.so, etc.) carry Python API
+// symbols (PyArg_ParseTuple, PyBool_FromLong, …) with no explicit library
+// dependency in their XCOFF loader section (IMPid = ".").  On AIX, such
+// unresolved symbols are looked up in the process-global symbol table, which
+// is populated only by libraries that appear in the XCOFF startup-load chain
+// (i.e. in the XCOFF loader section of the main executable or its startup-
+// linked dependencies).
+//
+// Without this file, libpython.so is loaded only via dlopen, transitively
+// through libdatadog-agent-three.so when rtloader initialises Python.  A
+// dlopen-loaded library does NOT add its symbols to the global symbol table.
+// As a result every Python C extension fails with:
+//
+//	ImportError: Symbol PyXxx is not exported from dependent module agent.
+//
+// Fix
+// ---
+// The init() function below calls C.Py_IsInitialized() once at process startup.
+// Go's CGO layer sees this Go→C call and emits a //go:cgo_import_dynamic
+// directive that places libpython.a(shr_64.o) in the agent binary's XCOFF
+// loader section.  Consequently libpython.so is loaded at process startup,
+// before any Python C extension module is imported, and all Python API
+// symbols enter the global symbol table where the extension modules can find them.
+//
+// Note: a C-internal reference (static void* holding &Py_IsInitialized) is NOT
+// sufficient — Go's linker only generates XCOFF import entries for symbols that
+// are called from the Go side through CGO.  A direct Go→C call is required.
+//
+// Py_IsInitialized() returns 0 when called here (Python not yet started) and
+// has no side effects — it is a safe, idempotent read of an internal flag.
+//
+// Part 2 — Exporting Python API symbols from the agent binary
+// The -bE:python.exp flag (passed via CGO_LDFLAGS at build time, NOT via
+// #cgo LDFLAGS which would be rejected by Go's CGO security filter) causes the
+// linker to add all Python API symbols to the agent binary's own EXP
+// (export) table.  Extension modules have Python API symbols with IMPid="."
+// in their XCOFF, meaning "find in the main program's EXP table".  Without
+// -bE, those symbols are not exported from the agent and every extension fails:
+//
+//	ImportError: Symbol PyXxx is not exported from dependent module agent.
+//
+// With -bE:python.exp, the agent exports the symbols and extensions load cleanly.
+
+/*
+#cgo LDFLAGS: -L${SRCDIR}/../../../embedded/lib -lpython3
+
+// Forward declaration — we do not include Python.h to avoid pulling in
+// the entire CPython header tree; Py_IsInitialized has a stable ABI.
+extern int Py_IsInitialized(void);
+*/
+import "C"
+
+func init() {
+	// Call Py_IsInitialized() to create a live Go→C reference.  This forces
+	// the CGO linker to emit a //go:cgo_import_dynamic for Py_IsInitialized,
+	// placing libpython.a(shr_64.o) in the XCOFF startup-load chain.
+	// Python is not yet started here so the call always returns 0; we discard
+	// the result.  There are no side effects.
+	_ = C.Py_IsInitialized()
+}

pkg/collector/python/tagger.go

@@ -16,7 +16,8 @@ import (
 )
 
 /*
-#cgo !windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo !aix,!windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo aix LDFLAGS: -ldl
 #cgo windows LDFLAGS: -ldatadog-agent-rtloader -lstdc++ -static
 
 #include "datadog_agent_rtloader.h"

pkg/collector/python/util.go

@@ -9,7 +9,8 @@ package python
 
 /*
 #include <datadog_agent_rtloader.h>
-#cgo !windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo !aix,!windows LDFLAGS: -ldatadog-agent-rtloader -ldl
+#cgo aix LDFLAGS: -ldl
 #cgo windows LDFLAGS: -ldatadog-agent-rtloader -lstdc++ -static
 */
 import "C"

rtloader/rtloader/api.cpp

@@ -42,6 +42,8 @@
 #    define DATADOG_AGENT_THREE "libdatadog-agent-three.dylib"
 #elif __FreeBSD__
 #    define DATADOG_AGENT_THREE "libdatadog-agent-three.so"
+#elif _AIX
+#    define DATADOG_AGENT_THREE "libdatadog-agent-three.so"
 #elif _WIN32
 #    define DATADOG_AGENT_THREE "libdatadog-agent-three.dll"
 #else
@@ -404,7 +406,11 @@ DATADOG_AGENT_RTLOADER_API int handle_crashes(const int enable_coredump, const i
         if (alt_stack == nullptr) {
             // Note: this memory is never freed, but it is necessary for the duration of the program
             alt_stack = _malloc(alt_stack_size);
-            stack_t new_stack{ .ss_sp = alt_stack, .ss_flags = 0, .ss_size = alt_stack_size };
+            stack_t new_stack;
+            memset(&new_stack, 0, sizeof(new_stack));
+            new_stack.ss_sp = (decltype(new_stack.ss_sp))alt_stack;
+            new_stack.ss_size = alt_stack_size;
+            new_stack.ss_flags = 0;
             int ret = sigaltstack(&new_stack, nullptr);
             if (ret != 0) {
                 std::ostringstream err_msg;