From 0697a4a55b7cf4dda0503e157886fe2b7178207f Mon Sep 17 00:00:00 2001
From: Randy Eckenrode <randy@largeandhighquality.com>
Date: Sat, 23 Mar 2024 09:18:53 -0400
Subject: [PATCH] ncnn: fix build on Darwin
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ncnn defaults to static linkage on Darwin against MoltenVK, but static
libraries are not build by default for MoltenVK in nixpkgs, and it’s not
taken as a dependency anyway. Override this behavior by specifying
`Vulkan_LIBRARY` explicitly as `-lvulkan` on Darwin.
---
 pkgs/development/libraries/ncnn/default.nix | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/pkgs/development/libraries/ncnn/default.nix b/pkgs/development/libraries/ncnn/default.nix
index 71b4bbc8fd42..88a6d042cbf4 100644
--- a/pkgs/development/libraries/ncnn/default.nix
+++ b/pkgs/development/libraries/ncnn/default.nix
@@ -33,7 +33,9 @@ stdenv.mkDerivation rec {
     "-DNCNN_BUILD_TOOLS=0"
     "-DNCNN_SYSTEM_GLSLANG=1"
     "-DNCNN_PYTHON=0" # Should be an attribute
-  ];
+  ]
+  # Requires setting `Vulkan_LIBRARY` on Darwin. Otherwise the build fails due to missing symbols.
+  ++ lib.optionals stdenv.isDarwin [ "-DVulkan_LIBRARY=-lvulkan" ];
 
   nativeBuildInputs = [ cmake ];
   buildInputs = [ vulkan-headers vulkan-loader glslang opencv protobuf ];