unrecognized command line option ‘-Wno-unknown-warning-option’

[strk]

Compiler used: gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0 Source commit hash: b4a786c910080d716cbf8c1230eada9077f118c2

[pramsey]

This option is new to GCC in version 8. It's been in clang for a while.

[gdt]

I have run into this with other projects. Basically, configure.ac ( :-) ) has to check each compiler option to see if it's really ok before adding it to CFLAGS. And, because one often wants -Werror, you have to add in -Werror first so that -Wfoo will fail compilation instead of giving a warning and being judged acceptable. And, if you don't want -Werror, I think one has to capture stderr, or use -Werror on the test calls.

[Paul Ramsey <pramsey@…>]

In 72b58fe/git:

Only use no-unknown-warning-option for Clang builds right now. References #1105