Attempt to unbreak docs.rs build
diff --git a/Cargo.toml b/Cargo.toml
index ac85670..0c7f03b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -19,6 +19,7 @@
 doctest = false
 
 [package.metadata.docs.rs]
+rustc-args = ["--cfg", "procmacro2_semver_exempt"]
 rustdoc-args = ["--cfg", "procmacro2_semver_exempt"]
 
 [dependencies]