facebook/hhvm — pull request #3774 by kristapsk (2014-09-17 13:29:59+00:00)
Title: Don't use system SQLite if headers not found.

Gentoo multilib environments may have situations when there is no 64-bit SQLite package installed but filesystem containts 32-bit libsqlite3.so and we have `LIBSQLITE3_LIBRARY` set, but not `LIBSQLITE3_INCLUDE_DIR` and `LIBSQLITE3_FOUND`. Don't try to use system SQLite headers if they are not present.

Fixes #3108.