diff --git a/build/moz.configure/rust.configure b/build/moz.configure/rust.configure
--- a/build/moz.configure/rust.configure
+++ b/build/moz.configure/rust.configure
@@ -119,6 +119,8 @@
     ambiguous = set()
     per_raw_os = {}
     for t in out:
+        if t.endswith("fuchsia"):
+            t = t + "-fuchsia"
         t = split_triplet(t, allow_unknown=True)
         key = (t.cpu, t.endianness, t.os)
         if key in per_os: