Allow libjulia to contain non-pointer variables

Before it was always creating the variables as a pointer
even if they are being referenced as a differnt type in the
internal library.

cli/jl_exports.h

@@ -5,9 +5,14 @@
 #include "../src/jl_exported_data.inc"
 #include "../src/jl_exported_funcs.inc"
 
-// Define data symbols as `const void * $(name);`
+// Define pointer data as `const void * $(name);`
 #define XX(name)    JL_DLLEXPORT const void * name;
-JL_EXPORTED_DATA(XX)
+JL_EXPORTED_DATA_POINTERS(XX)
+#undef XX
+
+// Define symbol data as `$type) $(name);`
+#define XX(name, type)    JL_DLLEXPORT type name;
+JL_EXPORTED_DATA_SYMBOLS(XX)
 #undef XX
 
 // Define holder locations for function addresses as `const void * $(name)_addr`

src/jl_exported_data.inc

@@ -1,4 +1,5 @@
-#define JL_EXPORTED_DATA(XX) \
+// Pointers that are exposed through the public libjulia
+#define JL_EXPORTED_DATA_POINTERS(XX) \
     XX(jl_abstractarray_type) \
     XX(jl_abstractslot_type) \
     XX(jl_abstractstring_type) \
@@ -62,7 +63,6 @@
     XX(jl_methoderror_type) \
     XX(jl_methtable_type) \
     XX(jl_module_type) \
-    XX(jl_n_threads) \
     XX(jl_namedtuple_type) \
     XX(jl_namedtuple_typename) \
     XX(jl_newvarnode_type) \
@@ -116,3 +116,8 @@
     XX(jl_void_type) \
     XX(jl_voidpointer_type) \
     XX(jl_weakref_type)
+
+
+// Data symbols that are defined inside the public libjulia
+#define JL_EXPORTED_DATA_SYMBOLS(XX) \
+    XX(jl_n_threads, int)