Magento 2 runs out of memory when removing secure base_url in database.

[pdenissen]

Preconditions

Magento 2.2.1
Runs on MacOS 10.13.2
PHP7.0.2
10.2.7-MariaDB
NGINX 1.12.1

Steps to reproduce

1. Fill both fields, secure and unsecure base URL, with something like http://environment.local/ in the CMS configuration.
2. Go to http://environment.local in your browser. Website should work now.
3. Open core_config_data with a database editor and search for the path web/secure/base_url
4. Replace the value http://environment.local/ with NULL.
5. Flush cache with bin/magento cache:flush in your terminal.
6. Open http://environment.local in your browser again (or refresh).
7. You should see a fatal error like: Fatal error: Allowed memory size of 1073741824 bytes exhausted (tried to allocate 262144 bytes) in app/code/Magento/Store/Model/Config/Placeholder.php on line 99

Expected result

1. Working website when go to http://environment.local

How to solve

Find web/secure/base_url in table core_config_data and copy the value from web/unsecure/base_url here.

Magento should not run out of memory because of a missing value I guess.

[magento-engcom-team]

@Hobbit78, thank you for your report.
We've created internal ticket(s) MAGETWO-85920 to track progress on the issue.

[p-bystritsky]

I think it's not a bug. You are directly adding the incorrect value to core_config_data. Magento cannot parse it, and it causes an infinite recursion. If you want to remove some value from core_config_data, you should delete the whole record, not only it's "value" raw.