# Below are the changes needed for generate-gn-build-files.sh
# except for depot_tools
# https://bugzilla.mozilla.org/show_bug.cgi?id=1654448

diff --git dom/media/webrtc/third_party_build/gn-configs/arm64_False_arm64_freebsd.mozconfig dom/media/webrtc/third_party_build/gn-configs/arm64_False_arm64_freebsd.mozconfig
new file mode 100644
index 0000000000..7c76576969
--- /dev/null
+++ dom/media/webrtc/third_party_build/gn-configs/arm64_False_arm64_freebsd.mozconfig
@@ -0,0 +1,12 @@
+export M4=/usr/local/bin/gm4
+export CC=/usr/local/bin/clang13
+export CXX=/usr/local/bin/clang++13
+export CPP=/usr/local/bin/clang-cpp13
+ac_add_options --prefix="/usr/local"
+ac_add_options --with-libclang-path="/usr/local/llvm13/lib"
+ac_add_options --with-wasi-sysroot="/usr/local/share/wasi-sysroot"
+
+ac_add_options --target=aarch64
+ac_add_options --enable-bootstrap
+
+mk_add_options MOZ_OBJDIR=obj-arm64_False_arm64_freebsd
diff --git dom/media/webrtc/third_party_build/gn-configs/arm64_True_arm64_freebsd.mozconfig dom/media/webrtc/third_party_build/gn-configs/arm64_True_arm64_freebsd.mozconfig
new file mode 100644
index 0000000000..d056686355
--- /dev/null
+++ dom/media/webrtc/third_party_build/gn-configs/arm64_True_arm64_freebsd.mozconfig
@@ -0,0 +1,13 @@
+export M4=/usr/local/bin/gm4
+export CC=/usr/local/bin/clang13
+export CXX=/usr/local/bin/clang++13
+export CPP=/usr/local/bin/clang-cpp13
+ac_add_options --prefix="/usr/local"
+ac_add_options --with-libclang-path="/usr/local/llvm13/lib"
+ac_add_options --with-wasi-sysroot="/usr/local/share/wasi-sysroot"
+
+ac_add_options --target=aarch64
+ac_add_options --enable-debug
+ac_add_options --enable-bootstrap
+
+mk_add_options MOZ_OBJDIR=obj-arm64_True_arm64_freebsd
diff --git dom/media/webrtc/third_party_build/gn-configs/generate-gn-build-files.sh dom/media/webrtc/third_party_build/gn-configs/generate-gn-build-files.sh
index 4452b0ce76..34a8ddf28e 100755
--- dom/media/webrtc/third_party_build/gn-configs/generate-gn-build-files.sh
+++ dom/media/webrtc/third_party_build/gn-configs/generate-gn-build-files.sh
@@ -57,17 +57,6 @@ set -eEuo pipefail
 
 SYS_NAME=`uname`
 
-# Check for modified files and abort if present.
-MODIFIED_FILES=`hg status --modified --added --exclude "**/moz.build" --exclude "dom/media/webrtc/third_party_build/**.json"`
-if [ "x$MODIFIED_FILES" = "x" ]; then
-  # Completely clean the mercurial checkout before proceeding
-  hg update -C -r .
-  hg purge
-else
-  echo "There are modified files in the checkout. Cowardly aborting!"
-  echo "$MODIFIED_FILES"
-  exit 1
-fi
 
 IS_WIN=0
 IS_DARWIN=0
@@ -94,6 +83,10 @@ elif [ "x$SYS_NAME" = "xMINGW32_NT-6.2" ]; then
   IS_WIN=1
 elif [ "x$SYS_NAME" = "xOpenBSD" ]; then
   CONFIGS="x64_False_x64_openbsd x64_True_x64_openbsd"
+elif [ "x$SYS_NAME" = "xFreeBSD" ]; then
+  CONFIGS="x64_False_x64_freebsd x64_True_x64_freebsd"
+  CONFIGS="$CONFIGS x64_False_x86_freebsd x64_True_x86_freebsd"
+  #CONFIGS="arm64_False_arm64_freebsd arm64_True_arm64_freebsd"
 else
   # Ensure rust has the correct targets for building x86 and arm64.  These
   # operations succeed quickly if previously completed.
diff --git dom/media/webrtc/third_party_build/gn-configs/x64_False_x64_freebsd.mozconfig dom/media/webrtc/third_party_build/gn-configs/x64_False_x64_freebsd.mozconfig
new file mode 100644
index 0000000000..37319939ba
--- /dev/null
+++ dom/media/webrtc/third_party_build/gn-configs/x64_False_x64_freebsd.mozconfig
@@ -0,0 +1,11 @@
+export M4=/usr/local/bin/gm4
+export CC=/usr/local/bin/clang13
+export CXX=/usr/local/bin/clang++13
+export CPP=/usr/local/bin/clang-cpp13
+ac_add_options --prefix="/usr/local"
+ac_add_options --with-libclang-path="/usr/local/llvm13/lib"
+ac_add_options --with-wasi-sysroot="/usr/local/share/wasi-sysroot"
+
+ac_add_options --enable-bootstrap
+
+mk_add_options MOZ_OBJDIR=obj-x64_False_x64_freebsd
diff --git dom/media/webrtc/third_party_build/gn-configs/x64_False_x86_freebsd.mozconfig dom/media/webrtc/third_party_build/gn-configs/x64_False_x86_freebsd.mozconfig
new file mode 100644
index 0000000000..4bcac5d797
--- /dev/null
+++ dom/media/webrtc/third_party_build/gn-configs/x64_False_x86_freebsd.mozconfig
@@ -0,0 +1,12 @@
+export M4=/usr/local/bin/gm4
+export CC=/usr/local/bin/clang13
+export CXX=/usr/local/bin/clang++13
+export CPP=/usr/local/bin/clang-cpp13
+ac_add_options --prefix="/usr/local"
+ac_add_options --with-libclang-path="/usr/local/llvm13/lib"
+ac_add_options --with-wasi-sysroot="/usr/local/share/wasi-sysroot"
+
+ac_add_options --target=i686
+ac_add_options --enable-bootstrap
+
+mk_add_options MOZ_OBJDIR=obj-x64_False_x86_freebsd
diff --git dom/media/webrtc/third_party_build/gn-configs/x64_True_x64_freebsd.mozconfig dom/media/webrtc/third_party_build/gn-configs/x64_True_x64_freebsd.mozconfig
new file mode 100644
index 0000000000..7c5ae25d67
--- /dev/null
+++ dom/media/webrtc/third_party_build/gn-configs/x64_True_x64_freebsd.mozconfig
@@ -0,0 +1,12 @@
+export M4=/usr/local/bin/gm4
+export CC=/usr/local/bin/clang13
+export CXX=/usr/local/bin/clang++13
+export CPP=/usr/local/bin/clang-cpp13
+ac_add_options --prefix="/usr/local"
+ac_add_options --with-libclang-path="/usr/local/llvm13/lib"
+ac_add_options --with-wasi-sysroot="/usr/local/share/wasi-sysroot"
+
+ac_add_options --enable-debug
+ac_add_options --enable-bootstrap
+
+mk_add_options MOZ_OBJDIR=obj-x64_True_x64_freebsd
diff --git dom/media/webrtc/third_party_build/gn-configs/x64_True_x86_freebsd.mozconfig dom/media/webrtc/third_party_build/gn-configs/x64_True_x86_freebsd.mozconfig
new file mode 100644
index 0000000000..ee95c64a23
--- /dev/null
+++ dom/media/webrtc/third_party_build/gn-configs/x64_True_x86_freebsd.mozconfig
@@ -0,0 +1,13 @@
+export M4=/usr/local/bin/gm4
+export CC=/usr/local/bin/clang13
+export CXX=/usr/local/bin/clang++13
+export CPP=/usr/local/bin/clang-cpp13
+ac_add_options --prefix="/usr/local"
+ac_add_options --with-libclang-path="/usr/local/llvm13/lib"
+ac_add_options --with-wasi-sysroot="/usr/local/share/wasi-sysroot"
+
+ac_add_options --target=i686
+ac_add_options --enable-debug
+ac_add_options --enable-bootstrap
+
+mk_add_options MOZ_OBJDIR=obj-x64_True_x86_freebsd
diff --git third_party/libwebrtc/build/config/BUILDCONFIG.gn third_party/libwebrtc/build/config/BUILDCONFIG.gn
index fe6f5b7d2a..1092f99c65 100644
--- third_party/libwebrtc/build/config/BUILDCONFIG.gn
+++ third_party/libwebrtc/build/config/BUILDCONFIG.gn
@@ -131,10 +131,12 @@ declare_args() {
   is_official_build = false
 
   # Whether we're a traditional desktop unix.
-  is_desktop_linux = current_os == "linux" || current_os == "openbsd"
+  is_desktop_linux = current_os == "linux" || current_os == "openbsd" ||
+                     current_os == "freebsd"
 
   # Set to true when compiling with the Clang compiler.
   is_clang = current_os != "linux" || current_os == "openbsd" ||
+             current_os == "freebsd" ||
              (current_cpu != "s390x" && current_cpu != "s390" &&
               current_cpu != "ppc64" && current_cpu != "ppc" &&
               current_cpu != "mips" && current_cpu != "mips64")
@@ -186,7 +188,7 @@ if (host_toolchain == "") {
   # TODO(dpranke): Add some sort of assert here that verifies that
   # no toolchain omitted host_toolchain from its toolchain_args().
 
-  if (host_os == "linux" || host_os == "openbsd") {
+  if (host_os == "linux" || host_os == "openbsd" || host_os == "freebsd" ) {
     if (target_os != "linux") {
       host_toolchain = "//build/toolchain/linux:clang_$host_cpu"
     } else if (is_clang) {
@@ -224,7 +226,8 @@ if (target_os == "android") {
   assert(host_os == "linux" || host_os == "mac",
          "Android builds are only supported on Linux and Mac hosts.")
   _default_toolchain = "//build/toolchain/android:android_clang_$target_cpu"
-} else if (target_os == "chromeos" || target_os == "linux" || target_os == "openbsd") {
+} else if (target_os == "chromeos" || target_os == "linux" ||
+           target_os == "openbsd" || target_os == "freebsd") {
   # See comments in build/toolchain/cros/BUILD.gn about board compiles.
   if (is_clang) {
     _default_toolchain = "//build/toolchain/linux:clang_$target_cpu"
@@ -289,7 +292,7 @@ is_chromeos = current_os == "chromeos"
 is_fuchsia = current_os == "fuchsia"
 is_ios = current_os == "ios"
 is_linux = current_os == "chromeos" || current_os == "linux"
-is_bsd = current_os == "openbsd"
+is_bsd = current_os == "openbsd" || current_os == "freebsd"
 is_mac = current_os == "mac"
 is_nacl = current_os == "nacl"
 is_win = current_os == "win" || current_os == "winuwp"