diff --git a/Makefile.include b/Makefile.include
index c16e016de87f1b53a6eefc6c8c1eb084209027e9..06ca9e5b6e2fbd6f931e1bcc9b6a82842013bf53 100644
--- a/Makefile.include
+++ b/Makefile.include
@@ -680,7 +680,8 @@ include $(RIOTTOOLS)/desvirt/Makefile.desvirt
 # The script will only touch the file if anything has changed since last time.
 $(RIOTBUILD_CONFIG_HEADER_C): FORCE
 	@mkdir -p '$(dir $@)'
-	$(Q)'$(RIOTTOOLS)/genconfigheader/genconfigheader.sh' '$@' $(CFLAGS_WITH_MACROS)
+	$(Q)'$(RIOTTOOLS)/genconfigheader/genconfigheader.sh' $(CFLAGS_WITH_MACROS) \
+		| '$(LAZYSPONGE)' $(LAZYSPONGE_FLAGS) '$@'
 
 CFLAGS_WITH_MACROS := $(CFLAGS)
 
diff --git a/dist/tools/genconfigheader/genconfigheader.sh b/dist/tools/genconfigheader/genconfigheader.sh
index bf17aef45c6633b0118a16097b0061ace237e350..581ceb55e0ce10580973f0819e3b084f34891d59 100755
--- a/dist/tools/genconfigheader/genconfigheader.sh
+++ b/dist/tools/genconfigheader/genconfigheader.sh
@@ -7,43 +7,18 @@
 # Public License v2.1. See the file LICENSE in the top level directory for more
 # details.
 #
-
-DEBUG=0
-if [ "${QUIET}" != "1" ]; then
-  DEBUG=1
-fi
-
-if [ $# -lt 1 ]; then
-  echo "Usage: $0 <output.h> [CFLAGS]..."
-  echo "Extract all macros from CFLAGS and generate a header file"
-  exit 1
-fi
-OUTPUTFILE="$1"
-shift
-
-MD5SUM=md5sum
-if [ "$(uname -s)" = "Darwin" -o "$(uname -s)" = "FreeBSD" ]; then
-  MD5SUM="md5 -r"
-fi
-
-# atomically update the file
-TMPFILE=
-trap '[ -n "${TMPFILE}" ] && rm -f "${TMPFILE}"' EXIT
-# Create temporary output file
-TMPFILE=$(mktemp ${OUTPUTFILE}.XXXXXX)
-
-if [ -z "${TMPFILE}" ]; then
-  echo "Error creating temporary file, aborting"
-  exit 1
-fi
+# Usage: $0 [CFLAGS]...
+#
+# Extract all macros from CFLAGS and generate a header file format"
+#
 
 # exit on any errors below this line
 set -e
 
-echo "/* DO NOT edit this file, your changes will be overwritten and won't take any effect! */" > "${TMPFILE}"
-echo "/* Generated from CFLAGS: $@ */" >> "${TMPFILE}"
+echo "/* DO NOT edit this file, your changes will be overwritten and won't take any effect! */"
+echo "/* Generated from CFLAGS: $@ */"
 
-[ -n "${LTOFLAGS}" ] && echo "/* LTOFLAGS=${LTOFLAGS} */" >> "${TMPFILE}"
+[ -n "${LTOFLAGS}" ] && echo "/* LTOFLAGS=${LTOFLAGS} */"
 
 for arg in "$@"; do
   case ${arg} in
@@ -54,34 +29,19 @@ for arg in "$@"; do
         # key=value pairs
         key=${d%%=*}
         value=${d#*=}
-        echo "#define $key $value" >> "${TMPFILE}"
+        echo "#define $key $value"
       else
         # simple #define
-        echo "#define $d 1" >> "${TMPFILE}"
+        echo "#define $d 1"
       fi
       ;;
     -U*)
       # Strip leading -U
       d=${arg#-U}
-      echo "#undef $d" >> "${TMPFILE}"
+      echo "#undef $d"
       ;;
     *)
       continue
       ;;
   esac
 done
-
-# Only replace old file if the new file differs. This allows make to check the
-# date of the config header for dependency calculations.
-NEWMD5=$(${MD5SUM} ${TMPFILE} | cut -c -32)
-OLDMD5=$(${MD5SUM} ${OUTPUTFILE} 2>/dev/null | cut -c -32)
-if [ "${NEWMD5}" != "${OLDMD5}" ]; then
-  if [ "${DEBUG}" -eq 1 ]; then echo "Replacing ${OUTPUTFILE} (${NEWMD5} != ${OLDMD5})"; fi
-  # Set mode according to umask
-  chmod +rw "${TMPFILE}"
-  mv -f "${TMPFILE}" "${OUTPUTFILE}"
-else
-  if [ "${DEBUG}" -eq 1 ]; then echo "Keeping old ${OUTPUTFILE}"; fi
-fi
-
-# $TMPFILE will be deleted by the EXIT trap above if it still exists when we exit