diff --git a/browser/config/tooltool-manifests/linux32/clang.manifest b/browser/config/tooltool-manifests/linux32/clang.manifest
index 992014d059c9..4e7c15753a9a 100644
--- a/browser/config/tooltool-manifests/linux32/clang.manifest
+++ b/browser/config/tooltool-manifests/linux32/clang.manifest
@@ -1,6 +1,6 @@
 [
 {
-"clang_version": "r166095"
+"clang_version": "r163716"
 },
 {
 "size": 47,
@@ -9,8 +9,8 @@
 "filename": "setup.sh"
 },
 {
-"size": 60425188,
-"digest": "c2dc850b858c0ccb32e2367b25cc5a4e9ec33929e8e896f546ffa983e553cfec5dcdf15deda7b501dd479fc4db4b1ef36d3e2583d782d857fd4ab3e01b98534b",
+"size": 61047821,
+"digest": "964837fd04d0ff7b0c01ca6ed8f3716256b9334e0d1200a7a06235bf837a75d41371d389b401cc15744ff509ecf96f31bdc0e679a0b3a6be93090673d5432ba4",
 "algorithm": "sha512",
 "filename": "clang.tar.bz2"
 }
diff --git a/browser/config/tooltool-manifests/linux64/clang.manifest b/browser/config/tooltool-manifests/linux64/clang.manifest
index 8be79be2d3de..2be84ab3e69f 100644
--- a/browser/config/tooltool-manifests/linux64/clang.manifest
+++ b/browser/config/tooltool-manifests/linux64/clang.manifest
@@ -1,6 +1,6 @@
 [
 {
-"clang_version": "r166095"
+"clang_version": "r163716"
 },
 {
 "size": 47,
@@ -9,8 +9,8 @@
 "filename": "setup.sh"
 },
 {
-"size": 60343264,
-"digest": "fe1a86f1b21030ef89bef83051b22dca22f0836c311a6e6565cb1115ed24dae654ad649d05c8f0a547dc8dfa2e94c4b694651a8da249c23532bf0944eddcb18d",
+"size": 61004559,
+"digest": "32d995275a00ed3f7ea79a4057c84108b2e1ebf13e89f05c96893b0e3602dc4891d962d8a61dbe5a395beb0fa6932ab90d5d3fa7eef7b95c092a7974e4cbd625",
 "algorithm": "sha512",
 "filename": "clang.tar.bz2"
 }
diff --git a/browser/config/tooltool-manifests/macosx32/releng.manifest b/browser/config/tooltool-manifests/macosx32/releng.manifest
index cf131da96956..9f326c9d0bce 100644
--- a/browser/config/tooltool-manifests/macosx32/releng.manifest
+++ b/browser/config/tooltool-manifests/macosx32/releng.manifest
@@ -1,6 +1,6 @@
 [
 {
-"clang_version": "r166095"
+"clang_version": "r163716"
 },
 {
 "size": 47,
@@ -9,8 +9,8 @@
 "filename": "setup.sh"
 },
 {
-"size": 53958161,
-"digest": "a75243cae46f29842c8c4de367df48a0ce4205621601beb50412d8e4b41b173285edae0dab7e51d303999ed6105ceb65d8bdf4721ae4a59d359da48933026b29",
+"size": 54033946,
+"digest": "50eb6fa636403f444bab10aee2370f1ac624a1e0105566639c7c266e784dbc6e4cd3901bbd11f53c4c63b2a6d2d07a603b3d9c333f5049bdc7a816b7d225631b",
 "algorithm": "sha512",
 "filename": "clang.tar.bz2"
 }
diff --git a/browser/config/tooltool-manifests/macosx64/releng.manifest b/browser/config/tooltool-manifests/macosx64/releng.manifest
index cf131da96956..9f326c9d0bce 100644
--- a/browser/config/tooltool-manifests/macosx64/releng.manifest
+++ b/browser/config/tooltool-manifests/macosx64/releng.manifest
@@ -1,6 +1,6 @@
 [
 {
-"clang_version": "r166095"
+"clang_version": "r163716"
 },
 {
 "size": 47,
@@ -9,8 +9,8 @@
 "filename": "setup.sh"
 },
 {
-"size": 53958161,
-"digest": "a75243cae46f29842c8c4de367df48a0ce4205621601beb50412d8e4b41b173285edae0dab7e51d303999ed6105ceb65d8bdf4721ae4a59d359da48933026b29",
+"size": 54033946,
+"digest": "50eb6fa636403f444bab10aee2370f1ac624a1e0105566639c7c266e784dbc6e4cd3901bbd11f53c4c63b2a6d2d07a603b3d9c333f5049bdc7a816b7d225631b",
 "algorithm": "sha512",
 "filename": "clang.tar.bz2"
 }