Do not have stderr in the result of $(shell)
diff --git a/testcase/shell_stderr.mk b/testcase/shell_stderr.mk
new file mode 100644
index 0000000..0ce589f
--- /dev/null
+++ b/testcase/shell_stderr.mk
@@ -0,0 +1,4 @@
+FOO=$(shell echo SHOULD_NOT_BE_AFTER_ECHO 1>&2)
+
+test:
+	echo $(FOO)