5 files changed, 39 insertions, 9 deletions

diff --git a/CHANGELOG b/CHANGELOG
index 346dce7..14a97e7 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,10 @@
+## 0.1.1
+* fix incorrect `yaxpeax_arch::Arch` impl for `std`-enabled builds
+  (DecodeError did not implement `std::error::Error` in those build environments)
+
+## 0.1.0
+* target yaxpeax-arch 0.2.0
+
 ## 0.0.6
 * fix incorrect markdown in README.md
 
diff --git a/Cargo.toml b/Cargo.toml
index 54a13b1..00fd5ae 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 
 name = "yaxpeax-arm"
-version = "0.1.0"
+version = "0.1.1"
 authors = [ "iximeow <me@iximeow.net>" ]
 license = "0BSD"
 repository = "http://git.iximeow.net/yaxpeax-arm/"
@@ -19,6 +19,9 @@ name = "test"
 path = "test/test.rs"
 
 [features]
-default = ["use-serde"]
+default = ["std", "use-serde"]
+
+# opt-in for std-related Error impl - necessary to `?`-unwrap `DecodeError`.
+std = []
 
 use-serde = ["yaxpeax-arch/use-serde", "serde", "serde_derive"]
diff --git a/src/armv7.rs b/src/armv7.rs
index 82b7732..60c09d0 100644
--- a/src/armv7.rs
+++ b/src/armv7.rs
@@ -5,7 +5,7 @@
 //#[cfg(feature="use-serde")]
 //use serde::{Serialize, Deserialize};
 
-use std::fmt::{self, Display, Formatter};
+use core::fmt::{self, Display, Formatter};
 
 use yaxpeax_arch::{Arch, AddressDiff, Colorize, Decoder, LengthedInstruction, Reader, ReadError, NoColors, ShowContextual, YaxColors};
 
@@ -1583,6 +1583,15 @@ impl fmt::Display for DecodeError {
     }
 }
 
+#[cfg(feature = "std")]
+extern crate std;
+#[cfg(feature = "std")]
+impl std::error::Error for DecodeError {
+    fn description(&self) -> &str {
+        <Self as yaxpeax_arch::DecodeError>::description(self)
+    }
+}
+
 impl From<ReadError> for DecodeError {
     fn from(_e: ReadError) -> DecodeError {
         DecodeError::ExhaustedInput
@@ -2399,7 +2408,7 @@ impl Decoder<ARMv7> for InstDecoder {
                                     Operand::Reg(Reg::from_u8(R[1])),
                                 ];
                             }
-                            _ => { unreachable!(format!("mul upcode: {:x}", op)) }
+                            _ => { unreachable!("mul upcode: {:x}", op) }
                         }
                     } else {
                     // |c o n d|0 0 0 u|x x x x x x x x x x x x x x x x|1 u u 1|x x x x|
@@ -2539,7 +2548,7 @@ impl Decoder<ARMv7> for InstDecoder {
                                          * high bit and mid-bits of op all being 0 was checked
                                          * before reaching here.
                                          */
-                                        unreachable!(format!("load/store flags: {:x}", flags));
+                                        unreachable!("load/store flags: {:x}", flags);
                                     }
                                 }
                             }
diff --git a/src/armv8/a64.rs b/src/armv8/a64.rs
index 2ef75d8..16ed9c5 100644
--- a/src/armv8/a64.rs
+++ b/src/armv8/a64.rs
@@ -1,7 +1,7 @@
 //#[cfg(feature="use-serde")]
 //use serde::{Serialize, Deserialize};
 
-use std::fmt::{self, Display, Formatter};
+use core::fmt::{self, Display, Formatter};
 
 use yaxpeax_arch::{Arch, AddressDiff, Decoder, LengthedInstruction, Reader, ReadError, ShowContextual, YaxColors};
 
@@ -140,6 +140,15 @@ impl fmt::Display for DecodeError {
     }
 }
 
+#[cfg(feature = "std")]
+extern crate std;
+#[cfg(feature = "std")]
+impl std::error::Error for DecodeError {
+    fn description(&self) -> &str {
+        <Self as yaxpeax_arch::DecodeError>::description(self)
+    }
+}
+
 impl From<ReadError> for DecodeError {
     fn from(_e: ReadError) -> DecodeError {
         DecodeError::ExhaustedInput
@@ -1075,7 +1084,7 @@ impl Decoder<ARMv8> for InstDecoder {
             Section::DataProcessingSimd2,            // 1111
         ][(section_bits & 0x0f) as usize];
 
-        println!("word: {:#x}, bits: {:#b}", word, section_bits & 0xf);
+        // println!("word: {:#x}, bits: {:#b}", word, section_bits & 0xf);
 
         match section {
             Section::DataProcessingSimd |
@@ -1741,7 +1750,7 @@ impl Decoder<ARMv8> for InstDecoder {
                 let group_byte = word >> 23;
                 let group_bits = (group_byte & 0x03) | ((group_byte >> 1) & 0x04) | ((group_byte >> 2) & 0x18);
 
-                println!("Group byte: {:#b}, bits: {:#b}", group_byte, group_bits);
+                // println!("Group byte: {:#b}, bits: {:#b}", group_byte, group_bits);
                 match group_bits {
                     0b00000 => {
                         let Rt = (word & 0x1f) as u16;
@@ -2178,7 +2187,7 @@ impl Decoder<ARMv8> for InstDecoder {
                         let Rn = ((word >> 5) & 0x1f) as u16;
                         let size_opc = ((word >> 22) & 0x03) | ((word >> 28) & 0x0c);
                         let category = (word >> 10) & 0x03;
-                        println!("load/store: size_opc: {:#b}, category: {:#b}", size_opc, category);
+                        // println!("load/store: size_opc: {:#b}, category: {:#b}", size_opc, category);
                         if word & 0x200000 != 0 {
                             if category != 0b10 {
                                 inst.opcode = Opcode::Invalid;
diff --git a/src/lib.rs b/src/lib.rs
index 1c315bf..ad2eb01 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,3 +1,5 @@
+#![no_std]
+
 #[cfg(feature="use-serde")]
 #[macro_use] extern crate serde_derive;
 #[cfg(feature="use-serde")]