openpgp: Avoid allocation if nothing has to be done.

1 files changed, 4 insertions, 0 deletions

diff --git a/openpgp/src/packet/signature.rs b/openpgp/src/packet/signature.rs
index 3ecd43dd..e5fe662d 100644
--- a/openpgp/src/packet/signature.rs
+++ b/openpgp/src/packet/signature.rs
@@ -2062,6 +2062,10 @@ impl crate::packet::Signature {
     /// change the serialized representation of the signature as a
     /// side-effect of verifying the signature.
     pub fn add_missing_issuers(&mut self) -> Result<()> {
+        if self.additional_issuers.is_empty() {
+            return Ok(());
+        }
+
         let issuers = self.get_issuers();
         for id in std::mem::replace(&mut self.additional_issuers,
                                     Vec::with_capacity(0)) {