As a workaround you can try staging version of it where builder.sh was removed: $ nix develop nixpkgs/staging#pkgsStatic.stdenv.cc.cc.

I think nix develop assumes that $drv.args is -e stdenv/generic/default-builder.sh and sources that. You might be able to sourcce it manually.

nix develop also uses nixpkgs#bashInteractive instead of drv's bash and does many other ad-hoc things: https://github.com/NixOS/nix/blob/master/src/nix/develop.cc#L484

https://github.com/NixOS/nixpkgs/pull/238525

This change adds a flag to update shebang paths that point to the Nix store. This is particularly useful when a cross-compiled package uses same script at compile-time and run-time, but the interpreter must be changed since hostPlatform ≠ buildPlatform.

In reply to @p14:matrix.org
I want to try and debug the lack of an $AR variable set while building a package without incurring a full rebuild. Is there a good way to turn on tracing (set -x) while all the setup scripts run for nix develop? (context: https://github.com/NixOS/nixpkgs/pull/246577#issuecomment-1672980907)

My repro is to insert NIX_DEBUG = if bintoolsName == "llvm-binutils" then 6 else null; onto pkgs/build-support/bintools-wrapper/default.nix and then build for example pkgsLLVM.llvmPackages_15.compiler-rt-no-libc.stdenv.cc. It results in:

x86_64-unknown-linux-gnu-clang-wrapper> /nix/store/mldrk9c17hjsqjv938hp1192i7f56844-x86_64-unknown-linux-gnu-llvm-binutils-wrapper-15.0.7/nix-support/setup-hook: line 1: /nix/store/yl01rd58vp4m8bbhkihpk132cprfmx6f-expand-response-params/bin/expand-response-params: Permission denied

And the first line of setup-hook reads:

@expandResponseParams@ -> /nix/store/yl01rd58vp4m8bbhkihpk132cprfmx6f-expand-response-params/bin/expand-response-params

Wow, this is unfortunate. If I build:

nix build --rebuild pkgsLLVM.llvmPackages_15.compiler-rt-no-libc.stdenv.cc.bintools

I get:

-r--r--r-- 1 root root 0 Jan  1  1970 result/nix-support/setup-hook

Now if I try to determine why setup-hook is empty by setting the preHook to include 'set -x', then, it's non-empty and works correctly:

preHook = if bintoolsName == "llvm-binutils" then "set -x" else null;

What's going on?

Wow, this is unfortunate. If I build:

nix build --rebuild pkgsLLVM.llvmPackages_15.compiler-rt-no-libc.stdenv.cc.bintools

I get:

-r--r--r-- 1 root root 0 Jan  1  1970 result/nix-support/setup-hook

Now if I try to determine why setup-hook is empty by setting the preHook to include 'set -x', then, it's non-empty and works correctly:

preHook = if bintoolsName == "llvm-binutils" then "set -x" else null;

I end up with:

-r--r--r-- 1 root root 4781 Jan  1  1970 result/nix-support/setup-hook


What's going on?

Wow, this is unfortunate. If I build:

nix build --rebuild pkgsLLVM.llvmPackages_15.compiler-rt-no-libc.stdenv.cc.bintools

I get:

-r--r--r-- 1 root root 0 Jan  1  1970 result/nix-support/setup-hook

Now if I try to determine why setup-hook is empty by setting the preHook to include 'set -x', then, it's non-empty and works correctly:

preHook = if bintoolsName == "llvm-binutils" then "set -x" else null;

I end up with:

-r--r--r-- 1 root root 4781 Jan  1  1970 result/nix-support/setup-hook

What's going on?