diff --git a/src/check_type.cpp b/src/check_type.cpp
index 6c49b9b8b..64fb67723 100644
--- a/src/check_type.cpp
+++ b/src/check_type.cpp
@@ -1932,7 +1932,7 @@ bool check_procedure_type(CheckerContext *ctx, Type *type, Ast *proc_type_node,
 	switch (cc) {
 	case ProcCC_StdCall:
 	case ProcCC_FastCall:
-		if (arch != TargetArch_i386 || arch != TargetArch_amd64) {
+		if (arch != TargetArch_i386 && arch != TargetArch_amd64) {
 			error(proc_type_node, "Invalid procedure calling convention \"%s\" for target architecture, expected either i386 or amd64, got %.*s",
 			      proc_calling_convention_strings[cc], LIT(target_arch_names[arch]));
 		}