diff --git a/Cargo.lock b/Cargo.lock
index 320dbefd0..a419d1817 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -325,7 +325,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.15.43 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)",
  "synstructure 0.10.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -813,7 +813,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.15.43 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -940,7 +940,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "syn"
-version = "0.15.43"
+version = "0.15.44"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -955,7 +955,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.15.43 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -1332,7 +1332,7 @@ dependencies = [
 "checksum ssh2 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "dee822d619a700f98c4de3b5931f272ecc7cf2e924ceb2df47b61df4ae033a0c"
 "checksum stable_deref_trait 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "dba1a27d3efae4351c8051072d619e3ade2820635c3958d826bfea39d59b54c8"
 "checksum strsim 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
-"checksum syn 0.15.43 (registry+https://github.com/rust-lang/crates.io-index)" = "ee06ea4b620ab59a2267c6b48be16244a3389f8bfa0986bdd15c35b890b00af3"
+"checksum syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)" = "9ca4b3b69a77cbe1ffc9e198781b7acb0c7365a883670e8f1c1bc66fba79a5c5"
 "checksum synstructure 0.10.2 (registry+https://github.com/rust-lang/crates.io-index)" = "02353edf96d6e4dc81aea2d8490a7e9db177bf8acb0e951c24940bf866cb313f"
 "checksum syntex 0.42.2 (registry+https://github.com/rust-lang/crates.io-index)" = "0a30b08a6b383a22e5f6edc127d169670d48f905bb00ca79a00ea3e442ebe317"
 "checksum syntex_errors 0.42.0 (registry+https://github.com/rust-lang/crates.io-index)" = "04c48f32867b6114449155b2a82114b86d4b09e1bddb21c47ff104ab9172b646"