From 5a9f5ec038cc3ce924ca45df061aa6a4ce5139a9 Mon Sep 17 00:00:00 2001
From: Gaetan Lepage <gaetan@glepage.com>
Date: Sat, 10 Jan 2026 09:52:24 +0000
Subject: [PATCH] python3Packages.paddlepaddle: fix evaluation error when
 selecting unsupported cuda version

---
 .../python-modules/paddlepaddle/default.nix   | 28 +++++++++++--------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/pkgs/development/python-modules/paddlepaddle/default.nix b/pkgs/development/python-modules/paddlepaddle/default.nix
index 96bdf6a76480..fe0f6519409f 100644
--- a/pkgs/development/python-modules/paddlepaddle/default.nix
+++ b/pkgs/development/python-modules/paddlepaddle/default.nix
@@ -34,21 +34,25 @@ let
   version = sources.version;
   format = "wheel";
   pyShortVersion = "cp${builtins.replaceStrings [ "." ] [ "" ] python.pythonVersion}";
-  hash =
-    if cudaSupport then
-      sources."${stdenv.hostPlatform.system}"."gpu"."cu${
-        lib.replaceStrings [ "." ] [ "" ] cudaPackages.cudatoolkit.version
-      }"."${pyShortVersion}"
-    else
-      sources."${stdenv.hostPlatform.system}"."cpu"."${pyShortVersion}"
-        or (throw "Unsupported system: ${stdenv.hostPlatform.system}");
-  platform = sources."${stdenv.hostPlatform.system}".platform;
+  cudaVersion = "cu${lib.replaceStrings [ "." ] [ "" ] cudaPackages.cudatoolkit.version}";
+
+  throwSystem = throw "Unsupported system: ${stdenv.hostPlatform.system}";
+  systemSources = sources."${stdenv.hostPlatform.system}" or throwSystem;
+
+  supportedCudaVersions = lib.concatStringsSep ", " (builtins.attrNames systemSources.gpu);
+  throwCuda = throw "Unsupported CUDA version: ${cudaVersion}. Supported versions: ${supportedCudaVersions}";
+  platformSources =
+    if cudaSupport then systemSources.gpu.${cudaVersion} or throwCuda else systemSources.cpu;
+
+  throwPython = throw "Unsupported python version: ${pyShortVersion}";
+  hash = platformSources.${pyShortVersion} or throwPython;
+
+  platform = sources.${stdenv.hostPlatform.system}.platform;
+
   src =
     if cudaSupport then
       (fetchurl {
-        url = "https://paddle-whl.bj.bcebos.com/stable/cu${
-          lib.replaceStrings [ "." ] [ "" ] cudaPackages.cudatoolkit.version
-        }/paddlepaddle-gpu/paddlepaddle_gpu-${version}-${pyShortVersion}-${pyShortVersion}-linux_x86_64.whl";
+        url = "https://paddle-whl.bj.bcebos.com/stable/${cudaVersion}/paddlepaddle-gpu/paddlepaddle_gpu-${version}-${pyShortVersion}-${pyShortVersion}-linux_x86_64.whl";
         inherit hash;
       })
     else