pacman --debug -S pandoc
...
...
Total Installed Size:  660.50 MiB

:: Proceed with installation? [Y/n] 
debug: using cachedir: /var/cache/pacman/pkg/
debug: using cachedir: /var/cache/pacman/pkg/
checking keyring...
debug: GPGME version: 1.12.0
debug: GPGME engine info: file=/usr/bin/gpg, home=/etc/pacman.d/gnupg/
debug: looking up key BBE43771487328A9 locally
debug: key lookup success, key exists
debug: looking up key 94657AB20F2A092B locally
debug: key lookup success, key exists
debug: looking up key EEEEE2EEEE2EEEEE locally
debug: key lookup failed, unknown key
debug: looking up key A5E9288C4FA415FA locally
debug: key lookup failed, unknown key
debug: key BBE43771487328A9 found in cache
debug: key BBE43771487328A9 found in cache
debug: looking up key FC1B547C8D8172C8 locally
debug: key lookup failed, unknown key
debug: key BBE43771487328A9 found in cache
debug: key BBE43771487328A9 found in cache
debug: looking up key F99FFE0FEAE999BD locally
debug: key lookup failed, unknown key
debug: key BBE43771487328A9 found in cache
debug: looking up key 7A4E76095D8A52E4 locally
debug: key lookup failed, unknown key
debug: looking up key 6D1655C14CE1C13E locally
debug: key lookup failed, unknown key
debug: looking up key 786C63F330D7CB92 locally
debug: key lookup failed, unknown key
debug: looking up key 51E8B148A9999C34 locally
debug: key lookup failed, unknown key
debug: looking up key 426991CD8406FFF3 locally
debug: key lookup failed, unknown key
debug: looking up key 4A1AFC345EBE18F8 locally
debug: key lookup failed, unknown key
debug: looking up key B02854ED753E0F1F locally
debug: key lookup failed, unknown key
downloading required keys...
debug: looking up key EEEEE2EEEE2EEEEE remotely

error: segmentation fault
Please submit a full bug report with --debug if appropriate.