From feaee2ba170766cc905a6aa9c799f3105cdc8145 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20=27vesim=27=20Kuli=C5=84ski?= <vesim809@pm.me>
Date: Wed, 18 Sep 2024 05:10:36 +0200
Subject: [PATCH] cc: Add support for -Wp,

---
 src/clang_options_data.zig     |  2 +-
 src/main.zig                   | 34 ++++++++++++++++++++++++++++++++++
 tools/update_clang_options.zig |  4 ++++
 3 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/src/clang_options_data.zig b/src/clang_options_data.zig
index ad07b45500..f41a451333 100644
--- a/src/clang_options_data.zig
+++ b/src/clang_options_data.zig
@@ -7472,7 +7472,7 @@ joinpd1("mtp="),
 .{
     .name = "Wp,",
     .syntax = .comma_joined,
-    .zig_equivalent = .other,
+    .zig_equivalent = .wp,
     .pd1 = true,
     .pd2 = false,
     .psl = false,
diff --git a/src/main.zig b/src/main.zig
index 4a7f477106..95f1ad569b 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -1791,6 +1791,7 @@ fn buildOutputType(
             var c_out_mode: ?COutMode = null;
             var out_path: ?[]const u8 = null;
             var is_shared_lib = false;
+            var preprocessor_args = std.ArrayList([]const u8).init(arena);
             var linker_args = std.ArrayList([]const u8).init(arena);
             var it = ClangArgIterator.init(arena, all_args);
             var emit_llvm = false;
@@ -1946,6 +1947,24 @@ fn buildOutputType(
                         is_shared_lib = true;
                     },
                     .rdynamic => create_module.opts.rdynamic = true,
+                    .wp => {
+                        var split_it = mem.splitScalar(u8, it.only_arg, ',');
+                        while (split_it.next()) |preprocessor_arg| {
+                            if (preprocessor_arg.len >= 3 and
+                                preprocessor_arg[0] == '-' and
+                                preprocessor_arg[2] != '-')
+                            {
+                                if (mem.indexOfScalar(u8, preprocessor_arg, '=')) |equals_pos| {
+                                    const key = preprocessor_arg[0..equals_pos];
+                                    const value = preprocessor_arg[equals_pos + 1 ..];
+                                    try preprocessor_args.append(key);
+                                    try preprocessor_args.append(value);
+                                    continue;
+                                }
+                            }
+                            try preprocessor_args.append(preprocessor_arg);
+                        }
+                    },
                     .wl => {
                         var split_it = mem.splitScalar(u8, it.only_arg, ',');
                         while (split_it.next()) |linker_arg| {
@@ -2554,6 +2573,20 @@ fn buildOutputType(
                 }
             }
 
+            // Parse preprocessor args.
+            var preprocessor_args_it = ArgsIterator{
+                .args = preprocessor_args.items,
+            };
+            while (preprocessor_args_it.next()) |arg| {
+                if (mem.eql(u8, arg, "-MD") or mem.eql(u8, arg, "-MMD") or mem.eql(u8, arg, "-MT")) {
+                    disable_c_depfile = true;
+                    const cc_arg = try std.fmt.allocPrint(arena, "-Wp,{s},{s}", .{ arg, preprocessor_args_it.nextOrFatal() });
+                    try cc_argv.append(arena, cc_arg);
+                } else {
+                    fatal("unsupported preprocessor arg: {s}", .{arg});
+                }
+            }
+
             if (mod_opts.sanitize_c) |wsc| {
                 if (wsc and mod_opts.optimize_mode == .ReleaseFast) {
                     mod_opts.optimize_mode = .ReleaseSafe;
@@ -5771,6 +5804,7 @@ pub const ClangArgIterator = struct {
         shared,
         rdynamic,
         wl,
+        wp,
         preprocess_only,
         asm_only,
         optimize,
diff --git a/tools/update_clang_options.zig b/tools/update_clang_options.zig
index f21993fbd6..3d32e4c7e1 100644
--- a/tools/update_clang_options.zig
+++ b/tools/update_clang_options.zig
@@ -154,6 +154,10 @@ const known_options = [_]KnownOpt{
         .name = "Wl,",
         .ident = "wl",
     },
+    .{
+        .name = "Wp,",
+        .ident = "wp",
+    },
     .{
         .name = "Xlinker",
         .ident = "for_linker",