Index: yaxpeax-x86/test/bench.rs
===================================================================
--- yaxpeax-x86.orig/test/bench.rs
+++ yaxpeax-x86/test/bench.rs
@@ -93,7 +93,7 @@ fn do_decode_swathe() {
     loop {
         match decoder.decode_into(&mut result, &mut reader) {
             Ok(()) => {
-                #[cfg(feature = "capstone_bench")]
+                #[cfg(all(feature = "capstone_bench", feature = "fmt"))]
                 test::black_box(write!(&mut buf[..], "{}", result));
                 test::black_box(&result);
             },
Index: yaxpeax-x86/test/long_mode/descriptions.rs
===================================================================
--- yaxpeax-x86.orig/test/long_mode/descriptions.rs
+++ yaxpeax-x86/test/long_mode/descriptions.rs
@@ -165,7 +165,9 @@ fn test_annotations_under(decoder: &Inst
     let mut inst = Instruction::default();
     match decoder.decode_with_annotation(&mut inst, &mut reader, &mut sink) {
         Ok(()) => {
+            #[cfg(feature = "fmt")]
             let text = format!("{}", inst);
+            #[cfg(feature = "fmt")]
             assert!(
                 text == expected,
                 "display error for {}:\n  decoded: {:?} under decoder {}\n displayed: {}\n expected: {}\n",
@@ -230,7 +232,11 @@ fn test_annotations_under(decoder: &Inst
             }
 
             if failed {
+                #[cfg(not(feature = "fmt"))]
+                eprintln!("[!] annotation check failed, enable the fmt feature for more info");
+                #[cfg(feature = "fmt")]
                 eprintln!("[!] annotation check for {}, `{}`, failed:", hex, inst);
+                #[cfg(feature = "fmt")]
                 for ((bit_start, bit_end, desc), check) in matches {
                     let mut desc = format!("bit {}:{}; {}", bit_start, bit_end, desc);
                     while desc.len() < 60 {
@@ -254,6 +260,7 @@ fn test_annotations_under(decoder: &Inst
                     };
                     eprintln!(" - {}{}", desc, comment);
                 }
+                #[cfg(feature = "fmt")]
                 for check in extra_checks {
                     eprintln!(" !  \x1b[31mextra check\x1b[0m: {}", check);
                 }
@@ -279,6 +286,7 @@ fn test_annotations_under(decoder: &Inst
 }
 
 #[test]
+#[cfg(feature = "fmt")]
 fn test_modrm_decode() {
     test_annotations(&[0xff, 0xc0], "inc eax", &[
         AnnotationCheck::exact(11, 13, InnerDescription::Opcode(Opcode::INC)),