diff --git a/runtime/CMakeLists.txt b/runtime/CMakeLists.txt
index ca9e50f251..6a5edb34b4 100644
--- a/runtime/CMakeLists.txt
+++ b/runtime/CMakeLists.txt
@@ -38,7 +38,7 @@ set(BUILD_SHARED_LIBS     AUTO                                CACHE STRING "Whet
 set(D_FLAGS               -w;-de;-preview=dip1000;-preview=dtorfields;-preview=fieldwise CACHE STRING "Runtime D compiler flags, separated by ';'")
 set(D_EXTRA_FLAGS         ""                                  CACHE STRING "Runtime extra D compiler flags, separated by ';'")
 set(D_FLAGS_DEBUG         -g;-link-defaultlib-debug;-d-debug  CACHE STRING "Runtime D compiler flags (debug libraries), separated by ';'")
-set(D_FLAGS_RELEASE       -O3;-release;-femit-local-var-lifetime  CACHE STRING "Runtime D compiler flags (release libraries), separated by ';'")
+set(D_FLAGS_RELEASE       -O3;-ludicrous;-femit-local-var-lifetime  CACHE STRING "Runtime D compiler flags (release libraries), separated by ';'")
 set(COMPILE_ALL_D_FILES_AT_ONCE ON                            CACHE BOOL   "Compile all D files for the runtime libs in a single command line instead of separately. Disabling this is useful for many CPU cores and/or iterative development.")
 set(RT_ARCHIVE_WITH_LDC   ON                                  CACHE STRING "Whether to archive the static runtime libs via LDC instead of CMake archiver")
 set(RT_CFLAGS             ""                                  CACHE STRING "Runtime extra C compiler flags, separated by ' '")
diff --git a/runtime/druntime/Makefile b/runtime/druntime/Makefile
index df9543950f..e87c37a2c0 100644
--- a/runtime/druntime/Makefile
+++ b/runtime/druntime/Makefile
@@ -106,7 +106,7 @@ ifeq ($(BUILD),debug)
 	UDFLAGS += -g -debug
 	DFLAGS:=$(UDFLAGS)
 else
-	UDFLAGS += -O -release
+	UDFLAGS += -O -ludicrous
 	DFLAGS:=$(UDFLAGS) -inline # unittests don't compile with -inline
 endif
 
diff --git a/runtime/druntime/test/common.mak b/runtime/druntime/test/common.mak
index 10e3f949da..2eec034e8a 100644
--- a/runtime/druntime/test/common.mak
+++ b/runtime/druntime/test/common.mak
@@ -50,7 +50,7 @@ ifeq ($(BUILD),debug)
     DFLAGS+=-g -debug $(if $(findstring ldmd2,$(DMD)),-link-defaultlib-debug,)
     CFLAGS:=$(CFLAGS_BASE) $(if $(findstring $(OS),windows),/Zi,-g)
 else
-    DFLAGS+=-O -release
+    DFLAGS+=-O -ludicrous
     CFLAGS:=$(CFLAGS_BASE) $(if $(findstring $(OS),windows),/O2,-O3)
 endif
 CXXFLAGS_BASE:=$(CFLAGS_BASE)
diff --git a/runtime/druntime/test/profile/Makefile b/runtime/druntime/test/profile/Makefile
index 4c263336e3..dede58ca52 100644
--- a/runtime/druntime/test/profile/Makefile
+++ b/runtime/druntime/test/profile/Makefile
@@ -22,7 +22,7 @@ endif
 .PHONY: all clean
 all: $(addprefix $(ROOT)/,$(addsuffix .done,$(TESTS)))
 
-# LDC: enable assertions for BUILD=RELEASE (=> `-O -release`)
+# LDC: enable assertions for BUILD=RELEASE (=> `-O -ludicrous`)
 $(ROOT)/profile.done: DFLAGS+=-profile $(if $(findstring ldmd2,$(DMD)),-check=assert=on,)
 $(ROOT)/profile.done: $(ROOT)/%.done: $(ROOT)/%$(DOTEXE)
 	@echo Testing $*