diff --git a/tests/run.sh.in b/tests/run.sh.in
index 8006f3b..1d81f8b 100644
--- a/tests/run.sh.in
+++ b/tests/run.sh.in
@@ -49,145 +49,145 @@ if [ "$(uname -o)" = "Msys" ]; then
 fi
 
 # 1) overall 'is it working?' test
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1}; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1}; echo \$?" \
 	'1'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs foo" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs foo" \
 	'-lfoo'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --cflags --libs foo" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --cflags --libs foo" \
 	'-lfoo' '-I/usr/include/foo' '-fPIC'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --cflags --libs 'foo > 1.2'" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --cflags --libs 'foo > 1.2'" \
 	'-lfoo' '-I/usr/include/foo' '-fPIC'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --cflags --libs 'foo > 1.2 bar >= 1.3'" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --cflags --libs 'foo > 1.2 bar >= 1.3'" \
 	'-lfoo' '-I/usr/include/foo' '-fPIC'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --cflags --libs 'foo' '>' '1.2'" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --cflags --libs 'foo' '>' '1.2'" \
 	'-lfoo' '-I/usr/include/foo' '-fPIC'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exists 'foo > 1.2'; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exists 'foo > 1.2'; echo \$?" \
 	'0'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exists 'foo > 1.2.3'; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exists 'foo > 1.2.3'; echo \$?" \
 	'1'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exists 'foo' '>' '1.2'; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exists 'foo' '>' '1.2'; echo \$?" \
 	'0'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --uninstalled 'foo'; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --uninstalled 'foo'; echo \$?" \
 	'1'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --uninstalled 'omg'; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --uninstalled 'omg'; echo \$?" \
 	'0'
 run_test "${1} --modversion ${selfdir}/lib1/foo.pc" \
 	'1.2.3'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exists 'foo >= '; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exists 'foo >= '; echo \$?" \
 	'1'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exists 'tilde <= 1.0.0'; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exists 'tilde <= 1.0.0'; echo \$?" \
 	'1'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exists 'tilde = 1.0.0~rc1'; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exists 'tilde = 1.0.0~rc1'; echo \$?" \
 	'0'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exists 'tilde >= 1.0.0'; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exists 'tilde >= 1.0.0'; echo \$?" \
 	'0'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exists '' 'foo'; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exists '' 'foo'; echo \$?" \
 	'0'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs intermediary-1 intermediary-2" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs intermediary-1 intermediary-2" \
 	'-lintermediary-1 -lintermediary-2 -lfoo -lbar -lbaz'
 
 # 2) tests for PKG_CONFIG_PATH order
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1${PATH_SEP}${selfdir}/lib2 ${1} --libs foo" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1${PATH_SEP}${selfdir}/lib2' ${1} --libs foo" \
 	'-lfoo'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib2${PATH_SEP}${selfdir}/lib1 ${1} --libs foo" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1${PATH_SEP}${selfdir}/lib2' ${1} --libs bar" \
 	'-lbar'
 
 # 3) tests for 'Requires' and 'Requires.private'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs bar" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs bar" \
 	'-lfoo' '-lbar'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs --cflags baz" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs --cflags baz" \
 	'-lbaz' '-fPIC' '-I/usr/include/foo'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --static --libs baz" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --static --libs baz" \
 	'-lfoo' '-lbaz' '-lzee'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --static --libs argv-parse-2" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --static --libs argv-parse-2" \
 	'-pthread '
 
 # 4) tests for parser bugs
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs dos-lineendings" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs dos-lineendings" \
 	'-L/usr/lib/dos-lineendings -ldos-lineendings'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs argv-parse" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs argv-parse" \
 	'-llib-2 -lpthread'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exists -foo; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exists -foo; echo \$?" \
 	'1'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs argv-parse-3" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs argv-parse-3" \
 	'-llib-1'
 
 # 5) tests for other regressions
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --variable=includedir foo" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --variable=includedir foo" \
 	'/usr/include'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs-only-L cflags-libs-only" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs-only-L cflags-libs-only" \
 	'-L/usr/local/lib'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs-only-L --libs-only-l cflags-libs-only" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs-only-L --libs-only-l cflags-libs-only" \
 	'-lfoo'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --cflags-only-I --cflags-only-other cflags-libs-only" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --cflags-only-I --cflags-only-other cflags-libs-only" \
 	'-I/usr/local/include'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs incomplete; echo $?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs incomplete; echo $?" \
 	'0'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --cflags incomplete" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --cflags incomplete" \
 	' '
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs incomplete" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs incomplete" \
 	' '
 
 # 6) tests for builtins
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --modversion pkg-config" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --modversion pkg-config" \
 	'0.27'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --variable=prefix foo" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --variable=prefix foo" \
 	'/usr'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --define-variable=prefix=/test --variable=prefix foo" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --define-variable=prefix=/test --variable=prefix foo" \
 	'/test'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --variable=pcfiledir foo" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --variable=pcfiledir foo" \
 	"${selfdir}/lib1"
 
 # 7) tests for env modifiers
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 PKG_CONFIG_SYSROOT_DIR=/test ${1} --cflags baz" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' PKG_CONFIG_SYSROOT_DIR='/test' ${1} --cflags baz" \
 	'-I/test/usr/include/foo'
 
 # 8) tests for 'Conflicts'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs conflicts; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs conflicts; echo \$?" \
 	'0'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --ignore-conflicts --libs conflicts; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --ignore-conflicts --libs conflicts; echo \$?" \
 	'-lconflicts' '0'
 
 # 9) tests for --atleast-version (with and without trailing space)
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --atleast-version 1.0 foo; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --atleast-version 1.0 foo; echo \$?" \
 	'0'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --atleast-version 2.0 foo; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --atleast-version 2.0 foo; echo \$?" \
 	'1'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exact-version 1.0 foo; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exact-version 1.0 foo; echo \$?" \
 	'1'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exact-version 1.2.3 foo; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exact-version 1.2.3 foo; echo \$?" \
 	'0'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --max-version 1.0 foo; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --max-version 1.0 foo; echo \$?" \
 	'1'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --max-version 2.0 foo; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --max-version 2.0 foo; echo \$?" \
 	'0'
 
 #    tests for issue #20
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --atleast-version 1.0 'foo '; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --atleast-version 1.0 'foo '; echo \$?" \
 	'0'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --atleast-version 2.0 'foo '; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --atleast-version 2.0 'foo '; echo \$?" \
 	'1'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exact-version 1.0 'foo '; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exact-version 1.0 'foo '; echo \$?" \
 	'1'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --exact-version 1.2.3 'foo '; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --exact-version 1.2.3 'foo '; echo \$?" \
 	'0'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --max-version 1.0 'foo '; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --max-version 1.0 'foo '; echo \$?" \
 	'1'
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --max-version 2.0 'foo '; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --max-version 2.0 'foo '; echo \$?" \
 	'0'
 
 # test missing requires
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --cflags missing-require; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --cflags missing-require; echo \$?" \
 	'1'
 
 # test quoted #35
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --cflags quotes" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --cflags quotes" \
 	"-DQUOTED=\\\"bla\\\""
 
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs nolib; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs nolib; echo \$?" \
 	'0'
 
-run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --libs nocflag; echo \$?" \
+run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --libs nocflag; echo \$?" \
 	'0'
 
 # test 36 - running against file in CWD with no path
@@ -197,11 +197,11 @@ run_test "cp ${selfdir}/lib1/foo.pc . && ${1} --libs foo.pc; rm -f foo.pc" \
 
 # 10) tests for internal getopt implementation with options at the end
 if [ "x@STRICT_MODE@" = "xno" ]; then
-	run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} foo --libs" \
+	run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} foo --libs" \
 		'-lfoo'
-	run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} foo --cflags --libs" \
+	run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} foo --cflags --libs" \
 		'-lfoo' '-I/usr/include/foo' '-fPIC'
-	run_test "PKG_CONFIG_PATH=${selfdir}/lib1 ${1} --cflags foo --libs" \
+	run_test "PKG_CONFIG_PATH='${selfdir}/lib1' ${1} --cflags foo --libs" \
 		'-lfoo' '-I/usr/include/foo' '-fPIC'
 fi