3.6.6: compile time watnings

[kloczek]

gcc 14.x from fedora rawhide.
First just summary stats:

[tkloczko@pers-jacek SPECS]$ rpmbuild -ba libsass.spec --quiet 2>&1 | grep -- \\[-W | sed 's/.*\[//; s/\]//' | sort | uniq -c | sort -nr
   1921 -Woverloaded-virtual=
      1 -Walloc-size-larger-than=

[kloczek]

Please let me know if you want full stderr.