diff --git a/source/toy_common.h b/source/toy_common.h
index 6dbfeef..d31dc10 100644
--- a/source/toy_common.h
+++ b/source/toy_common.h
@@ -5,27 +5,37 @@
 #include <stdint.h>
 #include <stddef.h>
 
-
 //TOY_API is platform-dependant, and marks publicly usable API functions
-#if defined(__linux__) || defined(__MINGW32__) || defined(__GNUC__)
-
-//GCC support
-#define TOY_API extern
-
+#if defined(__GNUC__)
+	#define TOY_API extern
 #elif defined(_MSC_VER)
-
-//MSVC support
-#ifndef TOY_EXPORT
-#define TOY_API __declspec(dllimport)
+	#ifndef TOY_EXPORT
+		#define TOY_API __declspec(dllimport)
+	#else
+		#define TOY_API __declspec(dllexport)
+	#endif
 #else
-#define TOY_API __declspec(dllexport)
+	//generic solution
+	#define TOY_API extern
 #endif
 
+//TOY_BITNESS is used to encourage memory-cache friendliness
+//source: https://www.linuxquestions.org/questions/programming-9/c-preprocessor-define-for-32-vs-64-bit-long-int-4175658579/
+#if defined(__GNUC__)
+	#if defined(__x86_64)
+		#define TOY_BITNESS 64
+	#else
+		#define TOY_BITNESS 32
+	#endif
+#elif defined(_MSC_VER)
+	#if defined(_M_X64)
+		#define TOY_BITNESS 64
+	#else
+		#define TOY_BITNESS 32
+	#endif
 #else
-
-//generic
-#define TOY_API extern
-
+	//generic solution
+	#define TOY_BITNESS -1
 #endif
 
 //bytecode version specifiers, embedded as the header
diff --git a/tests/cases/test_ast.c b/tests/cases/test_ast.c
index 5da6b78..e9b08e5 100644
--- a/tests/cases/test_ast.c
+++ b/tests/cases/test_ast.c
@@ -3,7 +3,7 @@
 
 #include <stdio.h>
 
-int test_sizeof_ast() {
+int test_sizeof_ast_32bit() {
 #define TEST_SIZEOF(type, size) \
 	if (sizeof(type) != size) { \
 		fprintf(stderr, TOY_CC_ERROR "ERROR: sizeof(" #type ") is %d, expected %d\n" TOY_CC_RESET, (int)sizeof(type), size); \
@@ -223,12 +223,16 @@ int main() {
 	//run each test set, returning the total errors given
 	int total = 0, res = 0;
 
-	res = test_sizeof_ast();
+#if TOY_BITNESS == 32
+	res = test_sizeof_ast_32bit();
 	total += res;
 
 	if (res == 0) {
 		printf(TOY_CC_NOTICE "All good\n" TOY_CC_RESET);
 	}
+#else
+	fprintf(stderr, TOY_CC_WARN "WARNING: Skipping test_sizeof_ast_32bit(); Can't determine the 'bitness' of this platform\n" TOY_CC_RESET);
+#endif
 
 	res = test_type_emission();
 	total += res;