diff --git a/configure.ac b/configure.ac
index 3da6d4b..7b57762 100644
--- a/configure.ac
+++ b/configure.ac
@@ -6,6 +6,19 @@
 AM_INIT_AUTOMAKE([subdir-objects -Wall -Werror foreign dist-xz])
 AM_SILENT_RULES([yes])
 
+# Make sure the default CFLAGS of `-O2 -g` don't override CODE_COVERAGE_CFLAGS
+# It is important that this comes before AC_PROG_C{C,XX}, as we are attempting
+# to stop them from populating default CFLAGS and CXXFLAGS.
+AS_IF([test "x$enable_tests" = "xno"], [enable_code_coverage=no])
+AS_IF([test "x$enable_code_coverage" != "xno"], [
+    AS_IF([test "x${CXXFLAGS+set}" != "xset"], [
+        AC_SUBST(CXXFLAGS, [""])
+    ])
+    AS_IF([test "x${CFLAGS+set}" != "xset"], [
+        AC_SUBST(CFLAGS, [""])
+    ])
+])
+
 # Checks for programs.
 AC_PROG_CXX
 AM_PROG_AR
@@ -103,6 +116,13 @@
     AX_RESTORE_FLAGS_WITH_PREFIX(OLD, [LDFLAGS])
 ])
 
+# Code coverage
+AX_CODE_COVERAGE
+m4_ifdef([_AX_CODE_COVERAGE_RULES],
+    [AM_CONDITIONAL(AUTOCONF_CODE_COVERAGE_2019_01_06, [true])],
+    [AM_CONDITIONAL(AUTOCONF_CODE_COVERAGE_2019_01_06, [false])])
+AX_ADD_AM_MACRO_STATIC([])
+
 PKG_PROG_PKG_CONFIG
 AC_ARG_WITH([systemdsystemunitdir],
      [AS_HELP_STRING([--with-systemdsystemunitdir=DIR], [Directory for systemd service files])],,