gh-135906: Test more internal headers in test_cext/test_cppext (#144751)

Author: vstinner

Lib/test/test_cext/extension.c

@@ -15,16 +15,19 @@
 
 #ifdef TEST_INTERNAL_C_API
    // gh-135906: Check for compiler warnings in the internal C API.
-   // - Cython uses pycore_frame.h.
+   // - Cython uses pycore_critical_section.h, pycore_frame.h and
+   //   pycore_template.h.
    // - greenlet uses pycore_frame.h, pycore_interpframe_structs.h and
    //   pycore_interpframe.h.
+#  include "internal/pycore_critical_section.h"
 #  include "internal/pycore_frame.h"
 #  include "internal/pycore_gc.h"
 #  include "internal/pycore_interp.h"
 #  include "internal/pycore_interpframe.h"
 #  include "internal/pycore_interpframe_structs.h"
 #  include "internal/pycore_object.h"
 #  include "internal/pycore_pystate.h"
+#  include "internal/pycore_template.h"
 #endif
 
 #ifndef MODULE_NAME

Lib/test/test_cppext/extension.cpp

@@ -15,11 +15,20 @@
 
 #ifdef TEST_INTERNAL_C_API
    // gh-135906: Check for compiler warnings in the internal C API
+   // - Cython uses pycore_critical_section.h, pycore_frame.h and
+   //   pycore_template.h.
+   // - greenlet uses pycore_frame.h, pycore_interpframe_structs.h and
+   //   pycore_interpframe.h.
 #  include "internal/pycore_frame.h"
+#  include "internal/pycore_interpframe_structs.h"
+#  include "internal/pycore_template.h"
+
    // mimalloc emits compiler warnings on Windows.
 #  if !defined(MS_WINDOWS)
 #    include "internal/pycore_backoff.h"
 #    include "internal/pycore_cell.h"
+#    include "internal/pycore_critical_section.h"
+#    include "internal/pycore_interpframe.h"
 #  endif
 #endif