cannot link libpq on Mac M1 - postgresql

Question

I've been trying to run the Rust Diesel crate on my Macbook M1 and it doesn't work. The final part of the compilation gets broken by the following error:
= note: ld: warning: ignoring file /usr/local/Cellar/libpq/14.1/lib/libpq.dylib, building for macOS-arm64 but attempting to link with file built for macOS-x86_64
Undefined symbols for architecture arm64:
When I get the info for libpq I get the following:
maxwellflitton#Maxwells-MacBook-Pro vanguard % brew info libpq
libpq: stable 14.1 (bottled) [keg-only]
Postgres C API library
https://www.postgresql.org/docs/14/libpq.html
/usr/local/Cellar/libpq/14.1 (2,335 files, 27.8MB)
Poured from bottle on 2022-01-09 at 00:14:32
From: https://github.com/Homebrew/homebrew-core/blob/HEAD/Formula/libpq.rb
License: PostgreSQL
==> Dependencies
Required: krb5 ✔, openssl#1.1 ✔
==> Caveats
libpq is keg-only, which means it was not symlinked into /usr/local,
because conflicts with postgres formula.
If you need to have libpq first in your PATH, run:
echo 'export PATH="/usr/local/opt/libpq/bin:$PATH"' >> ~/.zshrc
For compilers to find libpq you may need to set:
export LDFLAGS="-L/usr/local/opt/libpq/lib"
export CPPFLAGS="-I/usr/local/opt/libpq/include"
I've tried installing with the following command:
RUSTFLAGS='-L /usr/local/Cellar/libpq/14.1/lib' cargo install diesel_cli --no-default-features --features postgres --force
But I still get the same error. Will it just be easier to wipe the whole thing and start again and if so how would I do this? Other people on the internet using the M1 seem to be able to get round the problem with a simple brew install libpq. Never had any issues with my previous intel mac. My ~/.cargo/config.toml has the following configuration:
[target.aarch64-apple-darwin]
rustflags = '-L /usr/local/Cellar/libpq/14.1/lib -L /opt/homebrew/lib'

Answer 1

Surprisingly this worked
brew install postgresql libpq
cargo clean
cargo build
cargo install diesel_cli --no-default-features --features postgres
I think it had to do with installing diesel-cli before installing the necessary dependencies. Cleaning the cargo dependencies and reinstalling worked for me

Answer 2

on my M1 mac, I installed the postgresql client and library with brew:
brew install postgresql libpq
and attempted to install diesel_cli again, this time it worked fine:
cargo install diesel_cli --no-default-features --features postgres
for some reason, simply installing libpq was not enough to install diesel_cli, i had to install the postgres library and the client.

Answer 3

Encountered a similar problem, and the issue was coming from my brew config (I restored my filesystem from my mac Intel) :
❯ brew config
...
macOS: 12.6-x86_64
...
Therefore, brew was downloading packages built for intel processors. I uninstalled and reinstalled brew following their website and now brew config is correct:
❯ brew config
...
macOS: 12.6-arm64
...
Hope this helps!

Answer 4

I have a Mac M1 and installed both postgresql and libpq with brew
I eventually succeeded in installing diesel_cli with these lines in my ~/.cargo/config.toml file
[target.aarch64-apple-darwin]
rustflags = '-L /opt/homebrew/opt/libpq/lib -L /opt/homebrew/lib'
source was https://github.com/diesel-rs/diesel/issues/2605