diff --git a/build/make/configure.sh b/build/make/configure.sh
index 35131b07b6461ca715507828b5c570f630c94d5d..3b6c919fd7ca67a76cdf1b8ebdd598679d90d8e8 100755
--- a/build/make/configure.sh
+++ b/build/make/configure.sh
@@ -378,7 +378,7 @@ EOF
 fmt_deps = sed -e 's;^__image.axf;\$(dir \$@)\$(notdir \$<).o \$@;' #hide
 EOF
     else cat >> $1 << EOF
-fmt_deps = sed -e 's;^\(.*\)\.o;\$(dir \$@)\1\$(suffix \$<).o \$@;' #hide
+fmt_deps = sed -e 's;^\([a-zA-Z0-9_]*\)\.o;\$(dir \$@)\1\$(suffix \$<).o \$@;'
 EOF
     fi