From c61c47faf261f2f2f7c8b8247612591fec3f9836 Mon Sep 17 00:00:00 2001
From: Mike Hommey <mh@glandium.org>
Date: Fri, 26 Jan 2024 11:11:48 +0900
Subject: [PATCH 1/2] Really try dylib when compiling for Apple platforms

Really fixes #84. This is what #85 intended, as far as I can tell, but
the logic was such that it didn't work for cross-compiles from e.g.
Linux (apple_to_apple would be false, leading to the build_zlib path
being taken)
---
 build.rs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/build.rs b/build.rs
index 1368a124..13396fb2 100644
--- a/build.rs
+++ b/build.rs
@@ -67,11 +67,10 @@ fn main() {
     // Apple platforms have libz.1.dylib, and it's usually available even when
     // cross compiling (via fat binary or in the target's Xcode SDK)
     let cross_compiling = target != host;
-    let apple_to_apple = host.contains("-apple-") && target.contains("-apple-");
     if target.contains("msvc")
         || target.contains("pc-windows-gnu")
         || want_static
-        || (cross_compiling && !apple_to_apple)
+        || (cross_compiling && !target.contains("-apple-"))
     {
         return build_zlib(&mut cfg, &target);
     }

From 213574142753055e208d0e946903696d862b412e Mon Sep 17 00:00:00 2001
From: Mike Hommey <mh@glandium.org>
Date: Fri, 26 Jan 2024 11:22:47 +0900
Subject: [PATCH 2/2] Disable debug info when compiling smoke test to detect
 system zlib

When compiling for Apple platforms, with the output set to /dev/null,
the test fails because clang invokes dsymutil on the output, and that
fails on /dev/null.

clang doesn't invoke dsymutil if compiling without debug info.
---
 build.rs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/build.rs b/build.rs
index 13396fb2..9bc2d04d 100644
--- a/build.rs
+++ b/build.rs
@@ -184,7 +184,11 @@ fn try_vcpkg() -> bool {
 
 fn zlib_installed(cfg: &mut cc::Build) -> bool {
     let mut cmd = cfg.get_compiler().to_command();
-    cmd.arg("src/smoke.c").arg("-o").arg("/dev/null").arg("-lz");
+    cmd.arg("src/smoke.c")
+        .arg("-g0")
+        .arg("-o")
+        .arg("/dev/null")
+        .arg("-lz");
 
     println!("running {:?}", cmd);
     if let Ok(status) = cmd.status() {