windows-gnu: Add support for -gcodeview flag

lib/std/Build/Module.zig

@@ -8,7 +8,7 @@ import_table: std.StringArrayHashMapUnmanaged(*Module),
 
 resolved_target: ?std.Build.ResolvedTarget = null,
 optimize: ?std.builtin.OptimizeMode = null,
-dwarf_format: ?std.dwarf.Format,
+debug_format: ?std.builtin.DebugFormat,
 
 c_macros: std.ArrayListUnmanaged([]const u8),
 include_dirs: std.ArrayListUnmanaged(IncludeDir),
@@ -219,7 +219,7 @@ pub const CreateOptions = struct {
     single_threaded: ?bool = null,
     strip: ?bool = null,
     unwind_tables: ?std.builtin.UnwindTables = null,
-    dwarf_format: ?std.dwarf.Format = null,
+    debug_format: ?std.builtin.DebugFormat = null,
     code_model: std.builtin.CodeModel = .default,
     stack_protector: ?bool = null,
     stack_check: ?bool = null,
@@ -259,7 +259,7 @@ pub fn init(
                 .optimize = options.optimize,
                 .link_libc = options.link_libc,
                 .link_libcpp = options.link_libcpp,
-                .dwarf_format = options.dwarf_format,
+                .debug_format = options.debug_format,
                 .c_macros = .{},
                 .include_dirs = .{},
                 .lib_paths = .{},
@@ -525,11 +525,17 @@ pub fn appendZigProcessFlags(
     try addFlag(zig_args, m.pic, "-fPIC", "-fno-PIC");
     try addFlag(zig_args, m.red_zone, "-mred-zone", "-mno-red-zone");
 
-    if (m.dwarf_format) |dwarf_format| {
-        try zig_args.append(switch (dwarf_format) {
-            .@"32" => "-gdwarf32",
-            .@"64" => "-gdwarf64",
-        });
+    if (m.debug_format) |debug_format| {
+        switch (debug_format) {
+            .strip => {},
+            .dwarf => |fmt| switch (fmt) {
+                .@"32" => try zig_args.append("-gdwarf32"),
+                .@"64" => try zig_args.append("-gdwarf64"),
+            },
+            .code_view => {
+                try zig_args.append("-gcodeview");
+            },
+        }
     }
 
     if (m.unwind_tables) |unwind_tables| {

lib/std/Build/Step/Compile.zig

@@ -657,7 +657,6 @@ pub fn producesPdbFile(compile: *Compile) bool {
         .windows, .uefi => {},
         else => return false,
     }
-    if (target.abi.isGnu()) return false;
     if (target.ofmt == .c) return false;
     if (compile.root_module.strip == true or
         (compile.root_module.strip == null and compile.root_module.optimize == .ReleaseSmall))

lib/std/builtin.zig

@@ -160,6 +160,14 @@ pub const OptimizeMode = enum {
 /// Deprecated; use OptimizeMode.
 pub const Mode = OptimizeMode;
 
+/// DebugFormat specifies which type of debug information to generate:
+pub const DebugFormat = union(enum) {
+    /// No debug information.
+    strip,
+    dwarf: std.dwarf.Format,
+    code_view,
+};
+
 /// The calling convention of a function defines how arguments and return values are passed, as well
 /// as any other requirements which callers and callees must respect, such as register preservation
 /// and stack alignment.

src/Compilation.zig

@@ -882,13 +882,13 @@ pub const cache_helpers = struct {
         addEmitLoc(hh, optional_emit_loc orelse return);
     }
 
-    pub fn addOptionalDebugFormat(hh: *Cache.HashHelper, x: ?Config.DebugFormat) void {
+    pub fn addOptionalDebugFormat(hh: *Cache.HashHelper, x: ?std.builtin.DebugFormat) void {
         hh.add(x != null);
         addDebugFormat(hh, x orelse return);
     }
 
-    pub fn addDebugFormat(hh: *Cache.HashHelper, x: Config.DebugFormat) void {
-        const tag: @typeInfo(Config.DebugFormat).@"union".tag_type.? = x;
+    pub fn addDebugFormat(hh: *Cache.HashHelper, x: std.builtin.DebugFormat) void {
+        const tag: @typeInfo(std.builtin.DebugFormat).@"union".tag_type.? = x;
         hh.add(tag);
         switch (x) {
             .strip, .code_view => {},

src/Compilation/Config.zig

@@ -56,7 +56,7 @@ import_memory: bool,
 export_memory: bool,
 shared_memory: bool,
 is_test: bool,
-debug_format: DebugFormat,
+debug_format: std.builtin.DebugFormat,
 root_strip: bool,
 root_error_tracing: bool,
 dll_export_fns: bool,
@@ -65,11 +65,6 @@ san_cov_trace_pc_guard: bool,
 
 pub const CFrontend = enum { clang, aro };
 
-pub const DebugFormat = union(enum) {
-    strip,
-    dwarf: std.dwarf.Format,
-    code_view,
-};
 
 pub const Options = struct {
     output_mode: std.builtin.OutputMode,
@@ -107,7 +102,7 @@ pub const Options = struct {
     import_memory: ?bool = null,
     export_memory: ?bool = null,
     shared_memory: ?bool = null,
-    debug_format: ?DebugFormat = null,
+    debug_format: ?std.builtin.DebugFormat = null,
     dll_export_fns: ?bool = null,
     rdynamic: ?bool = null,
     san_cov_trace_pc_guard: bool = false,
@@ -439,7 +434,7 @@ pub fn resolve(options: Options) ResolveError!Config {
         break :b false;
     };
 
-    const debug_format: DebugFormat = b: {
+    const debug_format: std.builtin.DebugFormat = b: {
         if (root_strip and !options.any_non_stripped) break :b .strip;
         if (options.debug_format) |x| break :b x;
         break :b switch (target.ofmt) {

src/clang_options_data.zig

@@ -4148,7 +4148,14 @@ flagpd1("g3"),
     .pd2 = false,
     .psl = false,
 },
-flagpd1("gcodeview"),
+.{
+    .name = "gcodeview",
+    .syntax = .flag,
+    .zig_equivalent = .gcodeview,
+    .pd1 = true,
+    .pd2 = false,
+    .psl = false,
+},
 flagpd1("gcodeview-command-line"),
 flagpd1("gcodeview-ghash"),
 flagpd1("gcolumn-info"),

src/main.zig

@@ -1538,7 +1538,10 @@ fn buildOutputType(
                         create_module.opts.debug_format = .{ .dwarf = .@"32" };
                     } else if (mem.eql(u8, arg, "-gdwarf64")) {
                         create_module.opts.debug_format = .{ .dwarf = .@"64" };
-                    } else if (mem.eql(u8, arg, "-fformatted-panics")) {
+                    } else if (mem.eql(u8, arg, "-gcodeview")) {
+                        create_module.opts.debug_format = .code_view;
+                    }
+                    else if (mem.eql(u8, arg, "-fformatted-panics")) {
                         // Remove this after 0.15.0 is tagged.
                         warn("-fformatted-panics is deprecated and does nothing", .{});
                     } else if (mem.eql(u8, arg, "-fno-formatted-panics")) {
@@ -2160,6 +2163,10 @@ fn buildOutputType(
                             try cc_argv.appendSlice(arena, it.other_args);
                         }
                     },
+                    .gcodeview => {
+                        mod_opts.strip = false;
+                        create_module.opts.debug_format = .code_view;
+                    },
                     .gdwarf32 => {
                         mod_opts.strip = false;
                         create_module.opts.debug_format = .{ .dwarf = .@"32" };
@@ -5776,6 +5783,7 @@ pub const ClangArgIterator = struct {
         asm_only,
         optimize,
         debug,
+        gcodeview,
         gdwarf32,
         gdwarf64,
         sanitize,

tools/update_clang_options.zig

@@ -252,6 +252,10 @@ const known_options = [_]KnownOpt{
         .name = "debug",
         .ident = "debug",
     },
+    .{
+        .name = "gcodeview",
+        .ident = "gcodeview",
+    },
     .{
         .name = "gdwarf32",
         .ident = "gdwarf32",