From 9d2abfcf52c544cb158c11fc2ff3b7b495608711 Mon Sep 17 00:00:00 2001
From: Brian Smith <brian@briansmith.org>
Date: Thu, 5 Oct 2023 08:30:39 -0700
Subject: [PATCH] build.rs: Set compiler C and CPP (preprocessor) flags in one
 place.

Apparently it is OK to set `-std=c1x` even when compiling assembly
code, so just set it no matter what we're compiling. This simplifies
the code and allows future simplification.

It's not clear why certain warnings were separated from the others.
Combine them too, for the same reasons.
---
 build.rs | 25 +++++--------------------
 1 file changed, 5 insertions(+), 20 deletions(-)

diff --git a/build.rs b/build.rs
index 94f45d1158..8a44d10384 100644
--- a/build.rs
+++ b/build.rs
@@ -102,27 +102,15 @@ const RING_TEST_SRCS: &[&str] = &[("crypto/constant_time_test.c")];
 
 const PREGENERATED: &str = "pregenerated";
 
-fn c_flags(compiler: &cc::Tool) -> &'static [&'static str] {
-    if !compiler.is_like_msvc() {
-        static NON_MSVC_FLAGS: &[&str] = &[
-            "-std=c1x", // GCC 4.6 requires "c1x" instead of "c11"
-            "-Wbad-function-cast",
-            "-Wnested-externs",
-            "-Wstrict-prototypes",
-        ];
-        NON_MSVC_FLAGS
-    } else {
-        &[]
-    }
-}
-
 fn cpp_flags(compiler: &cc::Tool) -> &'static [&'static str] {
     if !compiler.is_like_msvc() {
         static NON_MSVC_FLAGS: &[&str] = &[
+            "-std=c1x", // GCC 4.6 requires "c1x" instead of "c11"
             "-pedantic",
             "-pedantic-errors",
             "-Wall",
             "-Wextra",
+            "-Wbad-function-cast",
             "-Wcast-align",
             "-Wcast-qual",
             "-Wconversion",
@@ -133,10 +121,12 @@ fn cpp_flags(compiler: &cc::Tool) -> &'static [&'static str] {
             "-Winvalid-pch",
             "-Wmissing-field-initializers",
             "-Wmissing-include-dirs",
+            "-Wnested-externs",
             "-Wredundant-decls",
             "-Wshadow",
             "-Wsign-compare",
             "-Wsign-conversion",
+            "-Wstrict-prototypes",
             "-Wundef",
             "-Wuninitialized",
             "-Wwrite-strings",
@@ -584,12 +574,7 @@ fn cc(file: &Path, ext: &str, target: &Target, include_dir: &Path, out_file: &Pa
     let _ = c.include("include");
     let _ = c.include(include_dir);
     match ext {
-        "c" => {
-            for f in c_flags(&compiler) {
-                let _ = c.flag(f);
-            }
-        }
-        "S" => (),
+        "c" | "S" => (),
         e => panic!("Unsupported file extension: {:?}", e),
     };
     for f in cpp_flags(&compiler) {