diff --git a/Makefile.am b/Makefile.am
index 106d887..96e2ca4 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -80,6 +80,7 @@ EXTRA_DIST =	pkg.m4 \
 		tests/lib1/fragment-quoting-6.pc \
 		tests/lib1/fragment-quoting-7.pc \
 		tests/lib1/malformed-1.pc \
+		tests/lib1/malformed-quoting.pc \
 		tests/lib1/explicit-sysroot.pc \
 		tests/test_env.sh \
 		$(test_scripts) \
diff --git a/tests/lib1/malformed-quoting.pc b/tests/lib1/malformed-quoting.pc
new file mode 100644
index 0000000..b8a324e
--- /dev/null
+++ b/tests/lib1/malformed-quoting.pc
@@ -0,0 +1,4 @@
+Name: malformed-quoting
+Version: 1
+Description: None.
+Cflags: '-I/ABC
diff --git a/tests/regress.sh b/tests/regress.sh
index 6b7a34e..7da53e6 100755
--- a/tests/regress.sh
+++ b/tests/regress.sh
@@ -27,6 +27,7 @@ tests_init \
 	virtual_variable \
 	fragment_collision \
 	malformed_1 \
+	malformed_quoting \
 	explicit_sysroot
 
 case_sensitivity_body()
@@ -233,6 +234,12 @@ malformed_1_body()
 		pkgconf --validate --with-path="${selfdir}/lib1" malformed-1
 }
 
+malformed_quoting_body()
+{
+	atf_check -s exit:0 -o ignore \
+		pkgconf --validate --with-path="${selfdir}/lib1" malformed-quoting
+}
+
 explicit_sysroot_body()
 {
 	export PKG_CONFIG_SYSROOT_DIR=/sysroot