Index: uspace/Makefile.common
===================================================================
--- uspace/Makefile.common	(revision b5746a25ee86f909936875a9a1702d3819b41b84)
+++ uspace/Makefile.common	(revision 1848f8e4741731f1df7e2d2c9d8441d27ddb940b)
@@ -176,5 +176,5 @@
 COMMON_CFLAGS = $(INCLUDES_FLAGS) -O$(OPTIMIZATION) -imacros $(CONFIG_HEADER) \
 	-ffreestanding -fno-builtin -nostdlib -nostdinc -fexec-charset=UTF-8 \
-	-finput-charset=UTF-8 -D__$(ENDIANESS)__ -fno-common \
+	-finput-charset=UTF-8 -D__$(ENDIANESS)__ -D_HELENOS_SOURCE -fno-common \
 	-fdebug-prefix-map=$(realpath $(ROOT_PATH))=.
 
Index: uspace/lib/c/generic/malloc.c
===================================================================
--- uspace/lib/c/generic/malloc.c	(revision b5746a25ee86f909936875a9a1702d3819b41b84)
+++ uspace/lib/c/generic/malloc.c	(revision 1848f8e4741731f1df7e2d2c9d8441d27ddb940b)
@@ -33,6 +33,4 @@
 /** @file
  */
-
-#define _HELENOS_SOURCE
 
 #include <malloc.h>