diff --git a/build_scripts/qt/compilers/clang-gcc-common-switches.pri b/build_scripts/qt/compilers/clang-gcc-common-switches.pri
index fca9988..c7c2a83 100644
--- a/build_scripts/qt/compilers/clang-gcc-common-switches.pri
+++ b/build_scripts/qt/compilers/clang-gcc-common-switches.pri
@@ -9,3 +9,8 @@ QMAKE_CXXFLAGS += -Wnon-virtual-dtor
 QMAKE_CXXFLAGS += -Wcast-align -Wunused -Woverloaded-virtual -Wformat=2
 
 QMAKE_CXXFLAGS += -Wdouble-promotion
+
+# Enable Link Time Optimization
+QMAKE_CXXFLAGS += -flto
+# Clang LTO requires the gold linker instead of ld
+QMAKE_LFLAGS += -flto -fuse-ld=gold
diff --git a/build_scripts/qt/compilers/gcc.pri b/build_scripts/qt/compilers/gcc.pri
index 2c49bd5..f3e2f7a 100644
--- a/build_scripts/qt/compilers/gcc.pri
+++ b/build_scripts/qt/compilers/gcc.pri
@@ -31,3 +31,6 @@ QMAKE_CXXFLAGS += -Wduplicated-branches -Wduplicated-cond -Wlogical-op -Wrestric
 QMAKE_CXXFLAGS += -Wconversion -Wno-sign-conversion
 
 QMAKE_CXXFLAGS += -Wzero-as-null-pointer-constant
+
+# Qmake will append this even though higher optimization levels are used.
+QMAKE_LFLAGS_RELEASE -= -Wl,-O1