From 1364837d91fdf2647a7141f60ee8a78b1e1f16ff Mon Sep 17 00:00:00 2001
From: Randy Eckenrode <randy@largeandhighquality.com>
Date: Tue, 30 May 2023 15:20:39 -0400
Subject: [PATCH] unzip: fix configure script when using clang 16

Clang 16 makes implicit int and function declarations an error by
default in any mode except for C89. The configure script has two of
these that cause it to misdetect features when using Clang 16.

* Implicit `int main` in the errno check. This is fixed by adding the
  missing `int`.
* Implicit definitions of `opendir` and `closedir`. These are fixed by
  including the required headers.
---
 pkgs/tools/archivers/unzip/default.nix        |  4 ++++
 .../unzip/implicit-declarations-fix.patch     | 21 +++++++++++++++++++
 2 files changed, 25 insertions(+)
 create mode 100644 pkgs/tools/archivers/unzip/implicit-declarations-fix.patch

diff --git a/pkgs/tools/archivers/unzip/default.nix b/pkgs/tools/archivers/unzip/default.nix
index f61bc9df66d5..b0a4484e87f3 100644
--- a/pkgs/tools/archivers/unzip/default.nix
+++ b/pkgs/tools/archivers/unzip/default.nix
@@ -60,6 +60,9 @@ stdenv.mkDerivation rec {
       ];
       sha256 = "sha256-on79jElQ+z2ULWAq14RpluAqr9d6itHiZwDkKubBzTc=";
     })
+    # Clang 16 makes implicit declarations an error by default for C99 and newer, causing the
+    # configure script to fail to detect errno and the directory libraries on Darwin.
+    ./implicit-declarations-fix.patch
   ] ++ lib.optional enableNLS
     (fetchurl {
       url = "https://gitweb.gentoo.org/repo/gentoo.git/plain/app-arch/unzip/files/unzip-6.0-natspec.patch?id=56bd759df1d0c750a065b8c845e93d5dfa6b549d";
@@ -67,6 +70,7 @@ stdenv.mkDerivation rec {
       sha256 = "67ab260ae6adf8e7c5eda2d1d7846929b43562943ec4aff629bd7018954058b1";
     });
 
+
   nativeBuildInputs = [ bzip2 ];
   buildInputs = [ bzip2 ] ++ lib.optional enableNLS libnatspec;
 
diff --git a/pkgs/tools/archivers/unzip/implicit-declarations-fix.patch b/pkgs/tools/archivers/unzip/implicit-declarations-fix.patch
new file mode 100644
index 000000000000..df19bf1722f9
--- /dev/null
+++ b/pkgs/tools/archivers/unzip/implicit-declarations-fix.patch
@@ -0,0 +1,21 @@
+--- a/unix/configure	2009-04-16 15:25:12.000000000 -0400
++++ b/unix/configure	2023-05-30 15:18:33.670321348 -0400
+@@ -408,7 +408,7 @@
+ echo Check for errno declaration
+ cat > conftest.c << _EOF_
+ #include <errno.h>
+-main()
++int main()
+ {
+   errno = 0;
+   return 0;
+@@ -419,6 +419,8 @@
+ 
+ echo Check for directory libraries
+ cat > conftest.c << _EOF_
++#include <sys/types.h>
++#include <dirent.h>
+ int main() { return closedir(opendir(".")); }
+ _EOF_
+ 
+