From 1860b778a5a8abe503b0f6098d292514bc8560ae Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=F0=9D=91=B7=F0=9D=92=89=F0=9D=92=8A=F0=9D=92=8D?=
 =?UTF-8?q?=F0=9D=92=90=F0=9D=92=84=F0=9D=92=82=F0=9D=92=8D=F0=9D=92=9A?=
 =?UTF-8?q?=F0=9D=92=94=F0=9D=92=95?= <regime_skylark.0y@icloud.com>
Date: Tue, 12 May 2026 07:24:24 -0400
Subject: [PATCH] libfyaml: fixing pflag mismatched intention

the assumption of the code is that if there are no lib flags set, then
just use the fallback of lpthread.

BUT! The way libSystem passes to it nothing because it's trying to
communicate that it's taking care of it using PTHREAD_CFLAGS. It leads
to this weird situation where both are passed!
---
 pkgs/by-name/li/libfyaml/package.nix          |  4 ++++
 pkgs/by-name/li/libfyaml/pthread-darwin.patch | 12 ++++++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 pkgs/by-name/li/libfyaml/pthread-darwin.patch

diff --git a/pkgs/by-name/li/libfyaml/package.nix b/pkgs/by-name/li/libfyaml/package.nix
index 26cc0461020b..7a7e5dc089c6 100644
--- a/pkgs/by-name/li/libfyaml/package.nix
+++ b/pkgs/by-name/li/libfyaml/package.nix
@@ -34,6 +34,10 @@ stdenv.mkDerivation (finalAttrs: {
       url = "https://github.com/pantoniou/libfyaml/commit/9192deaac095f9881cc1e5756dede683f36b09d6.diff";
       hash = "sha256-cNL9wQtxIRg/ShZLJP4qHYNFRrYo9kRG+/U+3FiUeaI=";
     })
+    # On Darwin, AX_PTHREAD returns empty PTHREAD_LIBS with -pthread in PTHREAD_CFLAGS;
+    # don't force -lpthread when PTHREAD_CFLAGS already provides pthread support.
+    # Pending PR: https://github.com/pantoniou/libfyaml/pull/294
+    ./pthread-darwin.patch
   ];
 
   nativeBuildInputs = [
diff --git a/pkgs/by-name/li/libfyaml/pthread-darwin.patch b/pkgs/by-name/li/libfyaml/pthread-darwin.patch
new file mode 100644
index 000000000000..bada0d80d142
--- /dev/null
+++ b/pkgs/by-name/li/libfyaml/pthread-darwin.patch
@@ -0,0 +1,12 @@
+--- a/configure.ac
++++ b/configure.ac
+@@ -99,6 +99,7 @@
+ AX_PTHREAD([], [AC_MSG_ERROR("Missing required pthread support")])
+ 
+-# in some cases PTHREAD_LIBS is empty - force -lpthread */
+-if test "x$PTHREAD_LIBS" = "x"; then
++# In some cases PTHREAD_LIBS is empty; force -lpthread only when PTHREAD_CFLAGS
++# also provides no pthread support (e.g. on Darwin, -pthread in CFLAGS suffices).
++if test "x$PTHREAD_LIBS" = "x" && test "x$PTHREAD_CFLAGS" = "x"; then
+ 	PTHREAD_LIBS="-lpthread"
+ fi