diff --git a/Makefile.am b/Makefile.am
index 8a33b9e22..91ad16422 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -58,6 +58,7 @@ if CODE_COVERAGE_ENABLED
 		--ignore-errors source \
 		--no-checksum \
 		--compat-libtool \
+		--rc geninfo_unexecuted_blocks=1 \
 		--output-file $(CODE_COVERAGE_INFO)
 else
 	@echo "You need to run configure with --enable-code-coverage to enable code coverage"
diff --git a/m4/knot-code-coverage.m4 b/m4/knot-code-coverage.m4
index 430e1c455..669be287a 100644
--- a/m4/knot-code-coverage.m4
+++ b/m4/knot-code-coverage.m4
@@ -29,7 +29,7 @@ AC_DEFUN([AX_CODE_COVERAGE], [
 		changequote([,])
 	
 		dnl Add the coverage flags (clang, gcc)
-		CFLAGS="$CFLAGS --coverage"
-		LDFLAGS="$LDFLAGS --coverage"
+		CFLAGS="$CFLAGS --coverage -fprofile-update=atomic"
+		LDFLAGS="$LDFLAGS --coverage -fprofile-update=atomic"
 	])
 ]) # AC_CODE_COVERAGE