diff --git a/.docker/Dockerfile.alpine b/.docker/Dockerfile.alpine
index c0da64dc..9a9e2113 100644
--- a/.docker/Dockerfile.alpine
+++ b/.docker/Dockerfile.alpine
@@ -4,7 +4,7 @@ FROM $ARCH/alpine:latest
 
 ARG ARCH
 ARG TARGET_ARCHS
-ARG TOOLCHAIN_OPTIMIZE=s
+ARG TOOLCHAIN_OPTIMIZE=2
 
 RUN apk update
 RUN apk upgrade
diff --git a/.docker/build-linux.sh b/.docker/build-linux.sh
index f2c1ad5a..57ddcf51 100755
--- a/.docker/build-linux.sh
+++ b/.docker/build-linux.sh
@@ -287,7 +287,7 @@ if [[ "-$BUILD_TYPE-" == *-shared-* ]]; then
 fi
 
 if [[ "-$BUILD_TYPE-" == *-static-* ]]; then
-  _SYSROOT="/opt/cross/Os"
+  _SYSROOT="/opt/cross/O2"
   _MARCH="${CROSS_ARCH}"
   if [[ "$CROSS_ARCH" == "native" ]]; then
     _MARCH="${ARCH}"
diff --git a/.docker/install-static-libs.sh b/.docker/install-static-libs.sh
index a1619ee3..892dc9f4 100644
--- a/.docker/install-static-libs.sh
+++ b/.docker/install-static-libs.sh
@@ -261,7 +261,7 @@ cpu = '$CARCH'
 endian = '$endian'
 EOF
 
-    export SYSROOT="/opt/cross/Os"
+    export SYSROOT="/opt/cross/O2"
     export PATH="$SYSROOT/usr/lib/ccache/bin:$SYSROOT/usr/bin:$PATH"
     export WORKROOT="$HOME/pkgs"
 
diff --git a/.docker/install-toolchain.sh b/.docker/install-toolchain.sh
index c3350de5..3a8fe135 100644
--- a/.docker/install-toolchain.sh
+++ b/.docker/install-toolchain.sh
@@ -78,6 +78,7 @@ ORIGPATH="$PATH"
 
 export CC="/usr/bin/ccache /usr/bin/gcc"
 export CXX="/usr/bin/ccache /usr/bin/g++"
+export LD="/usr/bin/ld"
 
 for target_arch in ${TARGET_ARCH_STR//,/ }; do
     for OPT in ${OPTIMIZE_STR//,/ }; do
@@ -113,8 +114,9 @@ for target_arch in ${TARGET_ARCH_STR//,/ }; do
                 ;;
         esac
 
-        export CFLAGS="-O${OPT} -ffunction-sections -fdata-sections -fmerge-all-constants -fPIC"
-        export CXXFLAGS="$CFLAGS"
+        export BOOT_CFLAGS='-O2 -g0 -pipe'
+        export CFLAGS="-O${OPT} -ffunction-sections -fdata-sections -fmerge-all-constants -fomit-frame-pointer -fPIC"
+        export CXXFLAGS="$CFLAGS -fno-semantic-interposition"
         export LDFLAGS="-Wl,--gc-sections"
 
         SYSROOT="/opt/cross/O${OPT}"