diff --git a/dist-build/apple-xcframework.sh b/dist-build/apple-xcframework.sh
index bf1754e2..782e77f7 100755
--- a/dist-build/apple-xcframework.sh
+++ b/dist-build/apple-xcframework.sh
@@ -71,7 +71,7 @@ build_macos() {
 
   ## macOS arm64
   if [ "$APPLE_SILICON_SUPPORTED" = "true" ]; then
-    export CFLAGS="-Ofast -arch arm64 -mmacosx-version-min=${MACOS_VERSION_MIN}"
+    export CFLAGS="-O3 -arch arm64 -mmacosx-version-min=${MACOS_VERSION_MIN}"
     export LDFLAGS="-arch arm64 -mmacosx-version-min=${MACOS_VERSION_MIN}"
 
     make distclean >/dev/null 2>&1
@@ -81,7 +81,7 @@ build_macos() {
   fi
 
   ## macOS x86_64
-  export CFLAGS="-Ofast -arch x86_64 -mmacosx-version-min=${MACOS_VERSION_MIN}"
+  export CFLAGS="-O3 -arch x86_64 -mmacosx-version-min=${MACOS_VERSION_MIN}"
   export LDFLAGS="-arch x86_64 -mmacosx-version-min=${MACOS_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -96,7 +96,7 @@ build_ios() {
   export SDK="${BASEDIR}/SDKs/iPhoneOS.sdk"
 
   ## 32-bit iOS
-  export CFLAGS="-Ofast -mthumb -arch armv7 -isysroot ${SDK} -mios-version-min=${IOS_VERSION_MIN}"
+  export CFLAGS="-O3 -mthumb -arch armv7 -isysroot ${SDK} -mios-version-min=${IOS_VERSION_MIN}"
   export LDFLAGS="-mthumb -arch armv7 -isysroot ${SDK} -mios-version-min=${IOS_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -105,7 +105,7 @@ build_ios() {
   make -j${PROCESSORS} install || exit 1
 
   ## 32-bit armv7s iOS
-  export CFLAGS="-Ofast -mthumb -arch armv7s -isysroot ${SDK} -mios-version-min=${IOS_VERSION_MIN}"
+  export CFLAGS="-O3 -mthumb -arch armv7s -isysroot ${SDK} -mios-version-min=${IOS_VERSION_MIN}"
   export LDFLAGS="-mthumb -arch armv7s -isysroot ${SDK} -mios-version-min=${IOS_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -114,7 +114,7 @@ build_ios() {
   make -j${PROCESSORS} install || exit 1
 
   ## 64-bit iOS
-  export CFLAGS="-Ofast -arch arm64 -isysroot ${SDK} -mios-version-min=${IOS_VERSION_MIN}"
+  export CFLAGS="-O3 -arch arm64 -isysroot ${SDK} -mios-version-min=${IOS_VERSION_MIN}"
   export LDFLAGS="-arch arm64 -isysroot ${SDK} -mios-version-min=${IOS_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -130,7 +130,7 @@ build_ios_simulator() {
 
   ## arm64 simulator
   if [ "$APPLE_SILICON_SUPPORTED" = "true" ]; then
-    export CFLAGS="-Ofast -arch arm64 -isysroot ${SDK} -mios-simulator-version-min=${IOS_SIMULATOR_VERSION_MIN}"
+    export CFLAGS="-O3 -arch arm64 -isysroot ${SDK} -mios-simulator-version-min=${IOS_SIMULATOR_VERSION_MIN}"
     export LDFLAGS="-arch arm64 -isysroot ${SDK} -mios-simulator-version-min=${IOS_SIMULATOR_VERSION_MIN}"
 
     make distclean >/dev/null 2>&1
@@ -140,7 +140,7 @@ build_ios_simulator() {
   fi
 
   ## i386 simulator
-  export CFLAGS="-Ofast -arch i386 -isysroot ${SDK} -mios-simulator-version-min=${IOS_SIMULATOR_VERSION_MIN}"
+  export CFLAGS="-O3 -arch i386 -isysroot ${SDK} -mios-simulator-version-min=${IOS_SIMULATOR_VERSION_MIN}"
   export LDFLAGS="-arch i386 -isysroot ${SDK} -mios-simulator-version-min=${IOS_SIMULATOR_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -149,7 +149,7 @@ build_ios_simulator() {
   make -j${PROCESSORS} install || exit 1
 
   ## x86_64 simulator
-  export CFLAGS="-Ofast -arch x86_64 -isysroot ${SDK} -mios-simulator-version-min=${IOS_SIMULATOR_VERSION_MIN}"
+  export CFLAGS="-O3 -arch x86_64 -isysroot ${SDK} -mios-simulator-version-min=${IOS_SIMULATOR_VERSION_MIN}"
   export LDFLAGS="-arch x86_64 -isysroot ${SDK} -mios-simulator-version-min=${IOS_SIMULATOR_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -164,7 +164,7 @@ build_watchos() {
   export SDK="${BASEDIR}/SDKs/WatchOS.sdk"
 
   # 32-bit watchOS
-  export CFLAGS="-Ofast -mthumb -arch armv7k -isysroot ${SDK} -mwatchos-version-min=${WATCHOS_VERSION_MIN}"
+  export CFLAGS="-O3 -mthumb -arch armv7k -isysroot ${SDK} -mwatchos-version-min=${WATCHOS_VERSION_MIN}"
   export LDFLAGS="-mthumb -arch armv7k -isysroot ${SDK} -mwatchos-version-min=${WATCHOS_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -173,7 +173,7 @@ build_watchos() {
   make -j${PROCESSORS} install || exit 1
 
   ## 64-bit arm64_32 watchOS
-  export CFLAGS="-Ofast -mthumb -arch arm64_32 -isysroot ${SDK} -mwatchos-version-min=${WATCHOS_VERSION_MIN}"
+  export CFLAGS="-O3 -mthumb -arch arm64_32 -isysroot ${SDK} -mwatchos-version-min=${WATCHOS_VERSION_MIN}"
   export LDFLAGS="-mthumb -arch arm64_32 -isysroot ${SDK} -mwatchos-version-min=${WATCHOS_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -182,7 +182,7 @@ build_watchos() {
   make -j${PROCESSORS} install || exit 1
 
   ## 64-bit arm64 watchOS
-  export CFLAGS="-Ofast -mthumb -arch arm64 -isysroot ${SDK} -mwatchos-version-min=${WATCHOS_VERSION_MIN}"
+  export CFLAGS="-O3 -mthumb -arch arm64 -isysroot ${SDK} -mwatchos-version-min=${WATCHOS_VERSION_MIN}"
   export LDFLAGS="-mthumb -arch arm64 -isysroot ${SDK} -mwatchos-version-min=${WATCHOS_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -198,7 +198,7 @@ build_watchos_simulator() {
 
   ## arm64 simulator
   if [ "$APPLE_SILICON_SUPPORTED" = "true" ]; then
-    export CFLAGS="-Ofast -arch arm64 -isysroot ${SDK} -mwatchos-simulator-version-min=${WATCHOS_SIMULATOR_VERSION_MIN}"
+    export CFLAGS="-O3 -arch arm64 -isysroot ${SDK} -mwatchos-simulator-version-min=${WATCHOS_SIMULATOR_VERSION_MIN}"
     export LDFLAGS="-arch arm64 -isysroot ${SDK} -mwatchos-simulator-version-min=${WATCHOS_SIMULATOR_VERSION_MIN}"
 
     make distclean >/dev/null 2>&1
@@ -208,7 +208,7 @@ build_watchos_simulator() {
   fi
 
   ## i386 simulator
-  export CFLAGS="-Ofast -arch i386 -isysroot ${SDK} -mwatchos-simulator-version-min=${WATCHOS_SIMULATOR_VERSION_MIN}"
+  export CFLAGS="-O3 -arch i386 -isysroot ${SDK} -mwatchos-simulator-version-min=${WATCHOS_SIMULATOR_VERSION_MIN}"
   export LDFLAGS="-arch i386 -isysroot ${SDK} -mwatchos-simulator-version-min=${WATCHOS_SIMULATOR_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -217,7 +217,7 @@ build_watchos_simulator() {
   make -j${PROCESSORS} install || exit 1
 
   ## x86_64 simulator
-  export CFLAGS="-Ofast -arch x86_64 -isysroot ${SDK} -mwatchos-simulator-version-min=${WATCHOS_SIMULATOR_VERSION_MIN}"
+  export CFLAGS="-O3 -arch x86_64 -isysroot ${SDK} -mwatchos-simulator-version-min=${WATCHOS_SIMULATOR_VERSION_MIN}"
   export LDFLAGS="-arch x86_64 -isysroot ${SDK} -mwatchos-simulator-version-min=${WATCHOS_SIMULATOR_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -232,7 +232,7 @@ build_tvos() {
   export SDK="${BASEDIR}/SDKs/AppleTVOS.sdk"
 
   ## 64-bit tvOS
-  export CFLAGS="-Ofast -arch arm64 -isysroot ${SDK} -mtvos-version-min=${TVOS_VERSION_MIN}"
+  export CFLAGS="-O3 -arch arm64 -isysroot ${SDK} -mtvos-version-min=${TVOS_VERSION_MIN}"
   export LDFLAGS="-arch arm64 -isysroot ${SDK} -mtvos-version-min=${TVOS_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -248,7 +248,7 @@ build_tvos_simulator() {
 
   ## arm64 simulator
   if [ "$APPLE_SILICON_SUPPORTED" = "true" ]; then
-    export CFLAGS="-Ofast -arch arm64 -isysroot ${SDK} -mtvos-simulator-version-min=${TVOS_SIMULATOR_VERSION_MIN}"
+    export CFLAGS="-O3 -arch arm64 -isysroot ${SDK} -mtvos-simulator-version-min=${TVOS_SIMULATOR_VERSION_MIN}"
     export LDFLAGS="-arch arm64 -isysroot ${SDK} -mtvos-simulator-version-min=${TVOS_SIMULATOR_VERSION_MIN}"
 
     make distclean >/dev/null 2>&1
@@ -258,7 +258,7 @@ build_tvos_simulator() {
   fi
 
   ## x86_64 simulator
-  export CFLAGS="-Ofast -arch x86_64 -isysroot ${SDK} -mtvos-simulator-version-min=${TVOS_SIMULATOR_VERSION_MIN}"
+  export CFLAGS="-O3 -arch x86_64 -isysroot ${SDK} -mtvos-simulator-version-min=${TVOS_SIMULATOR_VERSION_MIN}"
   export LDFLAGS="-arch x86_64 -isysroot ${SDK} -mtvos-simulator-version-min=${TVOS_SIMULATOR_VERSION_MIN}"
 
   make distclean >/dev/null 2>&1
@@ -272,7 +272,7 @@ build_visionos() {
   export PATH="${BASEDIR}/usr/bin:$BASEDIR/usr/sbin:$PATH"
   export SDK="${BASEDIR}/SDKs/XROS.sdk"
 
-  export CFLAGS="-Ofast -arch arm64 -isysroot ${SDK}"
+  export CFLAGS="-O3 -arch arm64 -isysroot ${SDK}"
   export LDFLAGS="-arch arm64 -isysroot ${SDK}"
 
   make distclean >/dev/null 2>&1
@@ -287,7 +287,7 @@ build_visionos_simulator() {
   export SDK="${BASEDIR}/SDKs/XRSimulator.sdk"
 
   if [ "$APPLE_SILICON_SUPPORTED" = "true" ]; then
-    export CFLAGS="-Ofast -arch arm64 -isysroot ${SDK}"
+    export CFLAGS="-O3 -arch arm64 -isysroot ${SDK}"
     export LDFLAGS="-arch arm64 -isysroot ${SDK}"
 
     make distclean >/dev/null 2>&1
@@ -304,7 +304,7 @@ build_catalyst() {
 
   ## arm64 catalyst
   if [ "$APPLE_SILICON_SUPPORTED" = "true" ]; then
-    export CFLAGS="-Ofast -arch arm64 -target arm64-apple-ios13.1-macabi -isysroot ${SDK}"
+    export CFLAGS="-O3 -arch arm64 -target arm64-apple-ios13.1-macabi -isysroot ${SDK}"
     export LDFLAGS="-arch arm64 -target arm64-apple-ios13.1-macabi -isysroot ${SDK}"
 
     make distclean >/dev/null 2>&1
@@ -314,7 +314,7 @@ build_catalyst() {
   fi
 
   ## x86_64 catalyst
-  export CFLAGS="-Ofast -arch x86_64 -target x86_64-apple-ios13.1-macabi -isysroot ${SDK}"
+  export CFLAGS="-O3 -arch x86_64 -target x86_64-apple-ios13.1-macabi -isysroot ${SDK}"
   export LDFLAGS="-arch x86_64 -target x86_64-apple-ios13.1-macabi -isysroot ${SDK}"
 
   make distclean >/dev/null 2>&1
diff --git a/dist-build/macos.sh b/dist-build/macos.sh
index fed7f394..2d2e0302 100755
--- a/dist-build/macos.sh
+++ b/dist-build/macos.sh
@@ -14,7 +14,7 @@ PROCESSORS=${NPROCESSORS:-3}
 
 mkdir -p $PREFIX || exit 1
 
-export CFLAGS="-mmacosx-version-min=${MACOS_VERSION_MIN} -Ofast"
+export CFLAGS="-mmacosx-version-min=${MACOS_VERSION_MIN} -O3"
 export LDFLAGS="-mmacosx-version-min=${MACOS_VERSION_MIN}"
 
 make distclean >/dev/null
diff --git a/dist-build/msys2-win32.sh b/dist-build/msys2-win32.sh
index 6e801404..6217bcc0 100755
--- a/dist-build/msys2-win32.sh
+++ b/dist-build/msys2-win32.sh
@@ -1,6 +1,6 @@
 #! /bin/sh
 
-export CFLAGS="-Ofast -fomit-frame-pointer -m32 -march=pentium3 -mtune=westmere"
+export CFLAGS="-O3 -fomit-frame-pointer -m32 -march=pentium3 -mtune=westmere"
 export PREFIX="$(pwd)/libsodium-win32"
 
 if (i686-w64-mingw32-gcc --version >/dev/null 2>&1); then
diff --git a/dist-build/msys2-win64.sh b/dist-build/msys2-win64.sh
index ef69047d..24b3072a 100755
--- a/dist-build/msys2-win64.sh
+++ b/dist-build/msys2-win64.sh
@@ -1,6 +1,6 @@
 #! /bin/sh
 
-export CFLAGS="-Ofast -fomit-frame-pointer -m64 -mtune=westmere"
+export CFLAGS="-O3 -fomit-frame-pointer -m64 -mtune=westmere"
 export PREFIX="$(pwd)/libsodium-win64"
 
 if (x86_64-w64-mingw32-gcc --version >/dev/null 2>&1); then