9 files changed, 36 insertions, 0 deletions

diff --git a/asm.s b/asm.s
index fd2c7fa..ed1ec3f 100644
--- a/asm.s
+++ b/asm.s
@@ -114,6 +114,13 @@ __sev:
   sev
   bx lr
 
+
+  .section .text.__udf
+  .global __udf
+  .thumb_func
+__udf:
+  udf
+
   .section .text.__wfe
   .global __wfe
   .thumb_func
diff --git a/bin/thumbv6m-none-eabi.a b/bin/thumbv6m-none-eabi.a
index 0684d4e..06a7cb7 100644
--- a/bin/thumbv6m-none-eabi.a
+++ b/bin/thumbv6m-none-eabi.a
diff --git a/bin/thumbv7em-none-eabi.a b/bin/thumbv7em-none-eabi.a
index cbfe5ae..48da24d 100644
--- a/bin/thumbv7em-none-eabi.a
+++ b/bin/thumbv7em-none-eabi.a
diff --git a/bin/thumbv7em-none-eabihf.a b/bin/thumbv7em-none-eabihf.a
index cbfe5ae..48da24d 100644
--- a/bin/thumbv7em-none-eabihf.a
+++ b/bin/thumbv7em-none-eabihf.a
diff --git a/bin/thumbv7m-none-eabi.a b/bin/thumbv7m-none-eabi.a
index 6e77aeb..296f66f 100644
--- a/bin/thumbv7m-none-eabi.a
+++ b/bin/thumbv7m-none-eabi.a
diff --git a/bin/thumbv8m.base-none-eabi.a b/bin/thumbv8m.base-none-eabi.a
index 44ee9af..026250b 100644
--- a/bin/thumbv8m.base-none-eabi.a
+++ b/bin/thumbv8m.base-none-eabi.a
diff --git a/bin/thumbv8m.main-none-eabi.a b/bin/thumbv8m.main-none-eabi.a
index 6590c92..6848518 100644
--- a/bin/thumbv8m.main-none-eabi.a
+++ b/bin/thumbv8m.main-none-eabi.a
diff --git a/bin/thumbv8m.main-none-eabihf.a b/bin/thumbv8m.main-none-eabihf.a
index 6590c92..6848518 100644
--- a/bin/thumbv8m.main-none-eabihf.a
+++ b/bin/thumbv8m.main-none-eabihf.a
diff --git a/src/asm.rs b/src/asm.rs
index 3d84341..b7ff19e 100644
--- a/src/asm.rs
+++ b/src/asm.rs
@@ -81,6 +81,35 @@ pub fn nop() {
     }
 }
 
+
+/// Generate an Undefined Instruction exception.
+///
+/// Can be used as a stable alternative to `core::intrinsics::abort`.
+#[inline]
+pub fn udf() -> ! {
+    match () {
+        #[cfg(all(cortex_m, feature = "inline-asm"))]
+        () => unsafe {
+            asm!("udf" :::: "volatile");
+            core::hint::unreachable_unchecked();
+        },
+
+        #[cfg(all(cortex_m, not(feature = "inline-asm")))]
+        () => unsafe {
+            extern "C" {
+                fn __udf();
+            }
+
+            __udf();
+
+            core::hint::unreachable_unchecked();
+        },
+
+        #[cfg(not(cortex_m))]
+        () => unimplemented!(),
+    }
+}
+
 /// Wait For Event
 #[inline]
 pub fn wfe() {