Add PYTHONMALLOC env var

Issue #26516:

* Add PYTHONMALLOC environment variable to set the Python memory
  allocators and/or install debug hooks.
* PyMem_SetupDebugHooks() can now also be used on Python compiled in release
  mode.
* The PYTHONMALLOCSTATS environment variable can now also be used on Python
  compiled in release mode. It now has no effect if set to an empty string.
* In debug mode, debug hooks are now also installed on Python memory allocators
  when Python is configured without pymalloc.

1 files changed, 9 insertions, 0 deletions

diff --git a/Programs/python.c b/Programs/python.c
index 37b10b837e..a7afbc774b 100644
--- a/Programs/python.c
+++ b/Programs/python.c
@@ -24,6 +24,9 @@ main(int argc, char **argv)
     int i, res;
     char *oldloc;
 
+    /* Force malloc() allocator to bootstrap Python */
+    (void)_PyMem_SetupAllocators("malloc");
+
     argv_copy = (wchar_t **)PyMem_RawMalloc(sizeof(wchar_t*) * (argc+1));
     argv_copy2 = (wchar_t **)PyMem_RawMalloc(sizeof(wchar_t*) * (argc+1));
     if (!argv_copy || !argv_copy2) {
@@ -62,7 +65,13 @@ main(int argc, char **argv)
 
     setlocale(LC_ALL, oldloc);
     PyMem_RawFree(oldloc);
+
     res = Py_Main(argc, argv_copy);
+
+    /* Force again malloc() allocator to release memory blocks allocated
+       before Py_Main() */
+    (void)_PyMem_SetupAllocators("malloc");
+
     for (i = 0; i < argc; i++) {
         PyMem_RawFree(argv_copy2[i]);
     }