Build fails with alire and GNAT 16

I ran into the following problem trying to get my first hello world project compiling using alr,
so take anything I say with a grain of salt.

I setup a simple hello_world project using alire and alire.toml and pointing it to aws using [[depends-on]] in alire.toml,
after having initialized it with "alr init --lib".

[[depends-on]]
aws = "*"

I then proceeded to try and build it.

I receive this error message:

   [Ada]          aws-services-callbacks.adb
   [Ada]          aws-services-dispatchers.ads
   [Ada]          aws-communication.adb
   [Ada]          aws-services-dispatchers-uri.adb
   [Ada]          aws-resources-streams-pipe.adb
aws-smtp-authentication-plain.adb:37:04: warning: use clause for package "Ada" has no effect [-gnatwu]

   compilation of aws-smtp-authentication-plain.adb failed

gprbuild: *** compilation phase failed

judging from other issues I encountered in this repository, I believe that this is a warning-treated-as-error, that can be fixed, by removing the use clause. (See #323)

This are my tools:

$ alr toolchain
CRATE       VERSION STATUS  NOTES              
gprbuild    26.0.1  Default 
gnat_native 16.1.0  Default

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 24.04.4 LTS
Release:        24.04
Codename:       noble

EDIT:
Same happens for other files:

aws-config.adb:39:04: warning: use clause for package "Ada" has no effect [-gnatwu]
aws-session.adb:47:04: warning: use clause for package "Streams" has no effect [-gnatwu]

As well as a new one:

gpr-compilation-protocol.adb:981:13: error: "time_t" is undefined

Start by reproducing the build from the reported alire.toml dependency with GNAT 16.1.0 and gprbuild 26.0.1, then inspect aws-smtp-authentication-plain.adb, aws-config.adb, aws-session.adb, and the reported gpr-compilation-protocol.adb failure. Done means the project builds successfully under the reported toolchain without these compilation failures.