diff --git a/src/compiler/codegen/CompilerCodegen.h b/src/compiler/codegen/CompilerCodegen.h
index 1b54be9..9537e46 100644
--- a/src/compiler/codegen/CompilerCodegen.h
+++ b/src/compiler/codegen/CompilerCodegen.h
@@ -51,7 +51,7 @@
 void oatInitializeRegAlloc(CompilationUnit* cUnit);
 
 /* Implemented in codegen/<target>/<target_variant>/ArchVariant.c */
-OatInstructionSetType oatInstructionSet(void);
+InstructionSet oatInstructionSet();
 
 /*
  * Implemented in codegen/<target>/<target_variant>/ArchVariant.c