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+#### Note: this error code is no longer emitted by the compiler.
+
+Cannot convert inline assembly operand to a single LLVM value.
+
+Erroneous code example:
+
+```ignore (no longer emitted)
+#![feature(llvm_asm)]
+
+fn main() {
+    unsafe {
+        llvm_asm!("" :: "r"("")); // error!
+    }
+}
+```
+
+This error usually happens when trying to pass in a value to an input inline
+assembly operand that is actually a pair of values. In particular, this can
+happen when trying to pass in a slice, for instance a `&str`. In Rust, these
+values are represented internally as a pair of values, the pointer and its
+length. When passed as an input operand, this pair of values can not be
+coerced into a register and thus we must fail with an error.