From 64282a7c68062c690a21ab403cd5a9fe9a7cd532 Mon Sep 17 00:00:00 2001
From: Alan Wu <XrXr@users.noreply.github.com>
Date: Thu, 30 May 2024 16:44:39 -0400
Subject: [PATCH] Build with `-Werror=implicit-function-declaration`

To prevent fail-fast in situations like
https://github.com/rust-lang/rust/issues/125619, where an upstream
source compiles but creates a link error way downstream.
---
 build.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/build.rs b/build.rs
index df98688d..e5503e88 100644
--- a/build.rs
+++ b/build.rs
@@ -327,6 +327,8 @@ mod c {
             // in https://github.com/rust-lang/compiler-rt/blob/c8fbcb3/cmake/config-ix.cmake#L19.
             cfg.flag_if_supported("-fomit-frame-pointer");
             cfg.define("VISIBILITY_HIDDEN", None);
+            // Avoid implicitly creating references to undefined functions
+            cfg.flag("-Werror=implicit-function-declaration");
         }
 
         // int_util.c tries to include stdlib.h if `_WIN32` is defined,