gh-91731: Don't define 'static_assert' in C++11 where is a keyword to avoid UB

Author: pablogsal

Include/pymacro.h

@@ -14,7 +14,7 @@
 // compiler support (gcc >= 4.6) and is called _Static_assert.
 #if (defined(__GLIBC__) \
      && (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 16)) \
-     && !defined(static_assert))
+     && !defined(static_assert) && !(defined(__cplusplus) && __cplusplus >= 201103L))
 #  define static_assert _Static_assert
 #endif
 

Misc/NEWS.d/next/Core and Builtins/2022-06-10-23-41-48.gh-issue-91731.fhYUQG.rst

@@ -0,0 +1,3 @@
+Avoid defining the ``static_assert`` when compiling with C++ 11, where this
+is a keyword and redefining it can lead to undefined behavior. Patch by
+Pablo Galindo