Index: uspace/lib/libc/Makefile.toolchain
===================================================================
--- uspace/lib/libc/Makefile.toolchain	(revision 9a0367fa3b9a9c76101f2153a0f10900ea972c2b)
+++ uspace/lib/libc/Makefile.toolchain	(revision 98a4e76b4160ea2db9e82981125a143f0b747421)
@@ -27,6 +27,5 @@
 #
 
-DEFS = -DARCH=$(ARCH)
-CFLAGS = -fno-builtin -Wall -Werror-implicit-function-declaration -Wmissing-prototypes -O3 -nostdlib -nostdinc -I$(LIBC_PREFIX)/include -pipe -g
+CFLAGS = -fno-builtin -Wall -Werror-implicit-function-declaration -Wmissing-prototypes -O3 -nostdlib -nostdinc -imacros $(LIBC_PREFIX)/../../../config.h -I$(LIBC_PREFIX)/include -pipe -g
 LFLAGS = -M -N $(SOFTINT_PREFIX)/libsoftint.a
 AFLAGS =
@@ -35,5 +34,7 @@
 #
 
--include $(LIBC_PREFIX)/arch/$(ARCH)/Makefile.inc
+-include $(LIBC_PREFIX)/../../../Makefile.config
+-include $(LIBC_PREFIX)/../../../config.defs
+-include $(LIBC_PREFIX)/arch/$(UARCH)/Makefile.inc
 
 ## Simple detection of the host system
@@ -59,4 +60,5 @@
 	OBJCOPY = $(BINUTILS_PREFIX)objcopy
 	OBJDUMP = $(BINUTILS_PREFIX)objdump
+	DEPEND_DEFS = $(DEFS) $(CONFIG_DEFS)
 endif
 
@@ -68,4 +70,5 @@
 	OBJCOPY = objcopy
 	OBJDUMP = objdump
+	DEPEND_DEFS = $(DEFS) $(CONFIG_DEFS)
 endif
 
@@ -77,4 +80,4 @@
 	OBJCOPY = $(TOOLCHAIN_DIR)/$(TARGET)-objcopy
 	OBJDUMP = $(TOOLCHAIN_DIR)/$(TARGET)-objdump
+	DEPEND_DEFS = $(DEFS) $(CONFIG_DEFS)
 endif
-