While Trying to install VirtualBox from AUR, and when installing the dependencies, I got this error.
==> Starting build()... /tmp/yaourt-tmp-keripix/aur-libpng12/libpng12/./PKGBUILD: line 26: patch: command not found ==> ERROR: Build Failed. Aborting... Error: Makepkg was unable to build libpng12 package.
It was solved by install base-devel package
sudo pacman -Sy base-devel
So, as a note to me, keep in mind that to install “build” packages from AUR, base-devel package is needed.