--- a/build/moz.configure/memory.configure
+++ b/build/moz.configure/memory.configure
@@ -73,8 +73,25 @@ def jemalloc_os_define(jemalloc, jemallo
 set_define(jemalloc_os_define, '1')
 
 @depends(jemalloc, jemalloc4, target)
 def jemalloc_os_define_android(jemalloc, jemalloc4, target):
     if jemalloc and not jemalloc4 and target.os == 'Android':
         return 'MOZ_MEMORY_ANDROID'
 
 set_define(jemalloc_os_define_android, '1')
+
+
+option('--enable-replace-malloc',
+       help='Enable ability to dynamically replace the malloc implementation')
+
+@depends('--enable-replace-malloc', jemalloc, milestone, build_project)
+def replace_malloc(value, jemalloc, milestone, build_project):
+    # Enable on central for the debugging opportunities it adds.
+    if milestone.is_nightly and jemalloc and build_project != 'js':
+        return True
+    if value and not jemalloc:
+        die('--enable-replace-malloc requires --enable-jemalloc')
+    return bool(value) or None
+
+set_config('MOZ_REPLACE_MALLOC', replace_malloc)
+set_define('MOZ_REPLACE_MALLOC', replace_malloc)
+add_old_configure_assignment('MOZ_REPLACE_MALLOC', replace_malloc)

--- a/build/moz.configure/old.configure
+++ b/build/moz.configure/old.configure
@@ -228,17 +228,16 @@ def old_configure_options(*options):
     '--enable-posix-nspr-emulation',
     '--enable-pref-extensions',
     '--enable-printing',
     '--enable-pulseaudio',
     '--enable-raw',
     '--enable-readline',
     '--enable-reflow-perf',
     '--enable-release',
-    '--enable-replace-malloc',
     '--enable-require-all-d3dc-versions',
     '--enable-rust',
     '--enable-safe-browsing',
     '--enable-sandbox',
     '--enable-signmar',
     '--enable-simulator',
     '--enable-skia',
     '--enable-skia-gpu',

--- a/old-configure.in
+++ b/old-configure.in
@@ -1143,18 +1143,16 @@ dnl ====================================
 dnl = Enable DMD
 dnl ========================================================
 
 if test "$MOZ_DMD"; then
     if test "${CPU_ARCH}" = "arm"; then
         CFLAGS="$CFLAGS -funwind-tables"
         CXXFLAGS="$CXXFLAGS -funwind-tables"
     fi
-
-    MOZ_REPLACE_MALLOC=1                # DMD enables replace-malloc
 fi
 
 dnl ========================================================
 dnl System overrides of the defaults for host
 dnl ========================================================
 case "$host" in
 *mingw*)
     if test -n "$_WIN32_MSVC"; then
@@ -5605,34 +5603,17 @@ Android|WINNT|Darwin)
   ;;
 *)
   dnl On !Android !Windows !OSX, we only want to link executables against mozglue
   MOZ_GLUE_IN_PROGRAM=1
   AC_DEFINE(MOZ_GLUE_IN_PROGRAM)
   ;;
 esac
 
-dnl ========================================================
-dnl = Enable dynamic replacement of malloc implementation
-dnl ========================================================
-if test -n "$NIGHTLY_BUILD" -a -n "$MOZ_MEMORY"; then
-  # Enable on central for the debugging opportunities it adds.
-  MOZ_REPLACE_MALLOC=1
-fi
-MOZ_ARG_ENABLE_BOOL(replace-malloc,
-[  --enable-replace-malloc   Enable ability to dynamically replace the malloc implementation],
-    MOZ_REPLACE_MALLOC=1,
-    MOZ_REPLACE_MALLOC= )
-
-if test -n "$MOZ_REPLACE_MALLOC" -a -z "$MOZ_MEMORY"; then
-    dnl We don't want to enable jemalloc unconditionally because it may be a
-    dnl deliberate choice not to enable it (bug 702250, for instance)
-    AC_MSG_ERROR([--enable-replace-malloc requires --enable-jemalloc])
-elif test -n "$MOZ_REPLACE_MALLOC"; then
-    AC_DEFINE(MOZ_REPLACE_MALLOC)
+if test -n "$MOZ_REPLACE_MALLOC"; then
     MOZ_SYSTEM_JEMALLOC=
 
     dnl Replace-malloc Mac linkage quirks
     if test -n "$MACOSX_DEPLOYMENT_TARGET"; then
         AC_CACHE_CHECK([how to do weak dynamic linking],
             ac_cv_weak_dynamic_linking,
             [echo 'extern void foo() __attribute__((weak_import));int bar() { if (foo) foo(); return 0; }' > conftest.c
              if AC_TRY_COMMAND([${CC-cc} -o conftest${DLL_SUFFIX} $CFLAGS -dynamiclib $LDFLAGS -Wl,-U,_foo conftest.c $LIBS 1>&5]) &&
@@ -5677,17 +5658,16 @@ elif test -n "$MOZ_REPLACE_MALLOC"; then
                  fi
              else
                  AC_ERROR([couldn't compile a simple C file])
              fi
              rm -rf conftest*])
         MOZ_REPLACE_MALLOC_LINKAGE="$ac_cv_weak_dynamic_linking"
     fi
 fi
-AC_SUBST(MOZ_REPLACE_MALLOC)
 AC_SUBST(MOZ_REPLACE_MALLOC_LINKAGE)
 
 dnl ========================================================
 dnl = Jemalloc build setup
 dnl ========================================================
 if test -z "$MOZ_MEMORY"; then
   case "${target}" in
     *-mingw*)

--- a/toolkit/moz.configure
+++ b/toolkit/moz.configure
@@ -61,16 +61,17 @@ def dmd(value):
     if value:
         return True
 
 set_config('MOZ_DMD', dmd)
 set_define('MOZ_DMD', dmd)
 add_old_configure_assignment('MOZ_DMD', dmd)
 imply_option('--enable-profiling', dmd)
 imply_option('--enable-jemalloc', dmd)
+imply_option('--enable-replace-malloc', dmd)
 
 # Javascript engine
 # ==============================================================
 include('../js/moz.configure')
 
 
 # L10N
 # ==============================================================