diff --git a/package/brltty/Config.in b/package/brltty/Config.in
index 288d9b56d8..48ceb04c99 100644
--- a/package/brltty/Config.in
+++ b/package/brltty/Config.in
@@ -3,6 +3,7 @@ config BR2_PACKAGE_BRLTTY
 	depends on BR2_USE_WCHAR
 	depends on BR2_TOOLCHAIN_HAS_THREADS
 	depends on !BR2_STATIC_LIBS
+	depends on BR2_USE_MMU # fork()
 	help
 	  A daemon providing access to the Linux console for a blind
 	  person using a refreshable braille display.
@@ -17,4 +18,5 @@ config BR2_PACKAGE_BRLTTY_TEXT_TABLE
 endif
 
 comment "brltty needs a toolchain w/ dynamic lib, threads, wchar"
+	depends on BR2_USE_MMU
 	depends on BR2_STATIC_LIBS || !BR2_TOOLCHAIN_HAS_THREADS || !BR2_USE_WCHAR