[0.29] Add configuration for the "nogil" CPython fork (GH-4912) (GH-4914)

Cython/Utility/ModuleSetupCode.c

@@ -46,6 +46,7 @@
   #define CYTHON_COMPILING_IN_PYPY 1
   #define CYTHON_COMPILING_IN_PYSTON 0
   #define CYTHON_COMPILING_IN_CPYTHON 0
+  #define CYTHON_COMPILING_IN_NOGIL 0
 
   #undef CYTHON_USE_TYPE_SLOTS
   #define CYTHON_USE_TYPE_SLOTS 0
@@ -91,6 +92,7 @@
   #define CYTHON_COMPILING_IN_PYPY 0
   #define CYTHON_COMPILING_IN_PYSTON 1
   #define CYTHON_COMPILING_IN_CPYTHON 0
+  #define CYTHON_COMPILING_IN_NOGIL 0
 
   #ifndef CYTHON_USE_TYPE_SLOTS
     #define CYTHON_USE_TYPE_SLOTS 1
@@ -133,10 +135,58 @@
     #define CYTHON_UPDATE_DESCRIPTOR_DOC 0
   #endif
 
+#elif defined(PY_NOGIL)
+  #define CYTHON_COMPILING_IN_PYPY 0
+  #define CYTHON_COMPILING_IN_PYSTON 0
+  #define CYTHON_COMPILING_IN_CPYTHON 0
+  #define CYTHON_COMPILING_IN_NOGIL 1
+
+  #ifndef CYTHON_USE_TYPE_SLOTS
+    #define CYTHON_USE_TYPE_SLOTS 1
+  #endif
+  #undef CYTHON_USE_PYTYPE_LOOKUP
+  #define CYTHON_USE_PYTYPE_LOOKUP 0
+  #ifndef CYTHON_USE_ASYNC_SLOTS
+    #define CYTHON_USE_ASYNC_SLOTS 1
+  #endif
+  #undef CYTHON_USE_PYLIST_INTERNALS
+  #define CYTHON_USE_PYLIST_INTERNALS 0
+  #ifndef CYTHON_USE_UNICODE_INTERNALS
+    #define CYTHON_USE_UNICODE_INTERNALS 1
+  #endif
+  #undef CYTHON_USE_UNICODE_WRITER
+  #define CYTHON_USE_UNICODE_WRITER 0
+  #undef CYTHON_USE_PYLONG_INTERNALS
+  #define CYTHON_USE_PYLONG_INTERNALS 0
+  #ifndef CYTHON_AVOID_BORROWED_REFS
+    #define CYTHON_AVOID_BORROWED_REFS 0
+  #endif
+  #ifndef CYTHON_ASSUME_SAFE_MACROS
+    #define CYTHON_ASSUME_SAFE_MACROS 1
+  #endif
+  #ifndef CYTHON_UNPACK_METHODS
+    #define CYTHON_UNPACK_METHODS 1
+  #endif
+  #undef CYTHON_FAST_THREAD_STATE
+  #define CYTHON_FAST_THREAD_STATE 0
+  #undef CYTHON_FAST_PYCALL
+  #define CYTHON_FAST_PYCALL 0
+  #ifndef CYTHON_PEP489_MULTI_PHASE_INIT
+    #define CYTHON_PEP489_MULTI_PHASE_INIT 1
+  #endif
+  #ifndef CYTHON_USE_TP_FINALIZE
+    #define CYTHON_USE_TP_FINALIZE 1
+  #endif
+  #undef CYTHON_USE_DICT_VERSIONS
+  #define CYTHON_USE_DICT_VERSIONS 0
+  #undef CYTHON_USE_EXC_INFO_STACK
+  #define CYTHON_USE_EXC_INFO_STACK 0
+
 #else
   #define CYTHON_COMPILING_IN_PYPY 0
   #define CYTHON_COMPILING_IN_PYSTON 0
   #define CYTHON_COMPILING_IN_CPYTHON 1
+  #define CYTHON_COMPILING_IN_NOGIL 0
 
   #ifndef CYTHON_USE_TYPE_SLOTS
     #define CYTHON_USE_TYPE_SLOTS 1

tests/compile/buildenv.pyx

@@ -36,6 +36,7 @@ cdef extern from *:
     cdef int CYTHON_COMPILING_IN_CPYTHON
     cdef int CYTHON_COMPILING_IN_PYPY
     cdef int CYTHON_COMPILING_IN_PYSTON
+    cdef int CYTHON_COMPILING_IN_NOGIL
     cdef int CYTHON_USE_PYLONG_INTERNALS
     cdef int CYTHON_USE_PYLIST_INTERNALS
     cdef int CYTHON_USE_UNICODE_INTERNALS
@@ -78,6 +79,7 @@ PY_VERSION_HEX  0x{PY_VERSION_HEX:X}
 CYTHON_COMPILING_IN_CPYTHON  {CYTHON_COMPILING_IN_CPYTHON}
 CYTHON_COMPILING_IN_PYPY  {CYTHON_COMPILING_IN_PYPY}
 CYTHON_COMPILING_IN_PYSTON  {CYTHON_COMPILING_IN_PYSTON}
+CYTHON_COMPILING_IN_NOGIL  {CYTHON_COMPILING_IN_NOGIL}
 
 CYTHON_USE_PYLONG_INTERNALS  {CYTHON_USE_PYLONG_INTERNALS}
 CYTHON_USE_PYLIST_INTERNALS  {CYTHON_USE_PYLIST_INTERNALS}