gmp and mpir missing package when Cross-Compiling gr-ettus

hi, i'm trying to install a usrp E312 using the follow guide:

{{{

https://kb.ettus.com/Software_Development_on_the_E3xx_USRP_-_Building_RFNoC_UHD_/_GNU_Radio_/_gr-ettus_from_Source#Cross-Compiling_gr-ettus

}}}

when i get to the cross-compiling gr-ettus step i get this error:

I make sure to set the environment correctly to use the SDK, and as far as i know, the gmp and mpir package are installed, so if someone can help me, i will appreciate it a lot.

thanks for your time

JGO