We have been experiencing the same problem with compiling Python-3.7.4 on a system with CentOS 7.6 (aka glib-2.17): Intel Compiler 2019.6 implements stdatomic.h. but lacks the definition of atomic_uintptr_t.

From a configure-point of view just failing to define HAVE_STDATOMIC_H would suffice.
Therefore just add another otherwise unused variable (which might warn & bail out in case of -Werror / -Werror-all)...

The following patch works for us to compile.

Granted, the "proper" way would be to add another configure check for the underlying type and not blurry the check for stdatomic.h -- but then again, Intel should just implement all of C11...