diff --git a/share/completions/rustc.fish b/share/completions/rustc.fish
index e6ab59085..d35c3b02d 100644
--- a/share/completions/rustc.fish
+++ b/share/completions/rustc.fish
@@ -28,17 +28,7 @@ complete -c rustc -f -l extern
 complete -c rustc -f -l sysroot
 complete -c rustc -x -l color -a 'auto always never'
 
-set -l rust_docs (rustc -C help 2>/dev/null \
-    | string replace -r -i '(\s+)-C(.+)(\s+)--(\s+)([^\n]+)' '$2 $5' \
-    | string trim \
-    | string match -r '^.*[^:]$')
-
-for line in $rust_docs
-    set -l docs (string split -m 1 ' ' -- $line)
-    set -l flag (string replace -r '^([a-z\-]+\=|[a-z\-]+)(.*)' '$1' \
-                                $docs[1])
-    complete -c rustc -x -s C -l codegen -a (string escape -- "$flag") -d "$docs[2]"
-end
+complete -c rustc -s C -l codegen -xa "(rustc -C help 2>/dev/null | string match -rv 'option is deprecated' | string replace -rf -i '(\s+)-C\s*(.+)=val(\s+)--(\s+)([^\n]+)' '\$2='\t'\$5')"
 
 # rustc -Z is only available with the nightly toolchain, which may not be installed
 if rustc +nightly >/dev/null 2>&1