Commit f09f960ce4

@@ -1313,10 +1313,8 @@ fn linkWithLLD(self: *Elf, comp: *Compilation) !void {
                 man.hash.addOptionalBytes(self.base.options.dynamic_linker);
             }
         }
-        if (is_dyn_lib) {
-            man.hash.addOptionalBytes(self.base.options.override_soname);
-            man.hash.addOptional(self.base.options.version);
-        }
+        man.hash.addOptionalBytes(self.base.options.soname);
+        man.hash.addOptional(self.base.options.version);
         man.hash.addStringSet(self.base.options.system_libs);
         man.hash.add(allow_shlib_undefined);
         man.hash.add(self.base.options.bind_global_refs_locally);
@@ -1505,13 +1503,10 @@ fn linkWithLLD(self: *Elf, comp: *Compilation) !void {
     }
 
     if (is_dyn_lib) {
-        const soname = self.base.options.override_soname orelse if (self.base.options.version) |ver|
-            try std.fmt.allocPrint(arena, "lib{}.so.{}", .{ self.base.options.root_name, ver.major })
-        else
-            try std.fmt.allocPrint(arena, "lib{}.so", .{self.base.options.root_name});
-        try argv.append("-soname");
-        try argv.append(soname);
-
+        if (self.base.options.soname) |soname| {
+            try argv.append("-soname");
+            try argv.append(soname);
+        }
         if (self.base.options.version_script) |version_script| {
             try argv.append("-version-script");
             try argv.append(version_script);

@@ -360,7 +360,7 @@ pub const InitOptions = struct {
     link_emit_relocs: bool = false,
     linker_script: ?[]const u8 = null,
     version_script: ?[]const u8 = null,
-    override_soname: ?[]const u8 = null,
+    soname: ?[]const u8 = null,
     linker_gc_sections: ?bool = null,
     linker_allow_shlib_undefined: ?bool = null,
     linker_bind_global_refs_locally: ?bool = null,
@@ -810,7 +810,7 @@ pub fn create(gpa: *Allocator, options: InitOptions) !*Compilation {
             .emit_relocs = options.link_emit_relocs,
             .rdynamic = options.rdynamic,
             .extra_lld_args = options.lld_argv,
-            .override_soname = options.override_soname,
+            .soname = options.soname,
             .version = options.version,
             .libc_installation = libc_dirs.libc_installation,
             .pic = pic,

@@ -911,13 +911,14 @@ fn buildSharedLib(
     const tracy = trace(@src());
     defer tracy.end();
 
+    const basename = try std.fmt.allocPrint(arena, "lib{s}.so.{d}", .{ lib.name, lib.sover });
     const emit_bin = Compilation.EmitLoc{
         .directory = bin_directory,
-        .basename = try std.fmt.allocPrint(arena, "lib{s}.so.{d}", .{ lib.name, lib.sover }),
+        .basename = basename,
     };
     const version: std.builtin.Version = .{ .major = lib.sover, .minor = 0, .patch = 0 };
     const ld_basename = path.basename(comp.getTarget().standardDynamicLinkerPath().get().?);
-    const override_soname = if (mem.eql(u8, lib.name, "ld")) ld_basename else null;
+    const soname = if (mem.eql(u8, lib.name, "ld")) ld_basename else basename;
     const map_file_path = try path.join(arena, &[_][]const u8{ bin_directory.path.?, all_map_basename });
     const c_source_files = [1]Compilation.CSourceFile{
         .{
@@ -955,7 +956,7 @@ fn buildSharedLib(
         .clang_passthrough_mode = comp.clang_passthrough_mode,
         .version = version,
         .version_script = map_file_path,
-        .override_soname = override_soname,
+        .soname = soname,
         .c_source_files = &c_source_files,
         .is_compiler_rt_or_libc = true,
     });

@@ -87,7 +87,7 @@ pub const Options = struct {
     subsystem: ?std.Target.SubSystem,
     linker_script: ?[]const u8,
     version_script: ?[]const u8,
-    override_soname: ?[]const u8,
+    soname: ?[]const u8,
     llvm_cpu_features: ?[*:0]const u8,
     /// Extra args passed directly to LLD. Ignored when not linking with LLD.
     extra_lld_args: []const []const u8,

@@ -304,6 +304,8 @@ const usage_build_generic =
     \\  --version-script [path]        Provide a version .map file
     \\  --dynamic-linker [path]        Set the dynamic interpreter path (usually ld.so)
     \\  --version [ver]                Dynamic library semver
+    \\  -fsoname[=name]                (linux) Override the default SONAME value
+    \\  -fno-soname                    (linux) Disable emitting a SONAME
     \\  -rdynamic                      Add all symbols to the dynamic symbol table
     \\  -rpath [path]                  Add directory to the runtime library search path
     \\  -feach-lib-rpath               Ensure adding rpath for each used dynamic library
@@ -348,6 +350,12 @@ const repl_help =
     \\
 ;
 
+const SOName = union(enum) {
+    no,
+    yes_default_value,
+    yes: []const u8,
+};
+
 const Emit = union(enum) {
     no,
     yes_default_path,
@@ -450,6 +458,7 @@ fn buildOutputType(
     var target_ofmt: ?[]const u8 = null;
     var output_mode: std.builtin.OutputMode = undefined;
     var emit_h: Emit = undefined;
+    var soname: SOName = undefined;
     var ensure_libc_on_non_freestanding = false;
     var ensure_libcpp_on_non_freestanding = false;
     var link_libc = false;
@@ -464,7 +473,6 @@ fn buildOutputType(
     var linker_script: ?[]const u8 = null;
     var version_script: ?[]const u8 = null;
     var disable_c_depfile = false;
-    var override_soname: ?[]const u8 = null;
     var linker_gc_sections: ?bool = null;
     var linker_allow_shlib_undefined: ?bool = null;
     var linker_bind_global_refs_locally: ?bool = null;
@@ -561,6 +569,8 @@ fn buildOutputType(
             //    .translate_c, .zig_test, .run => emit_h = .no,
             //    else => unreachable,
             //}
+
+            soname = .yes_default_value;
             const args = all_args[2..];
             var i: usize = 0;
             args_loop: while (i < args.len) : (i += 1) {
@@ -821,6 +831,12 @@ fn buildOutputType(
                         use_clang = false;
                     } else if (mem.eql(u8, arg, "-rdynamic")) {
                         rdynamic = true;
+                    } else if (mem.eql(u8, arg, "-fsoname")) {
+                        soname = .yes_default_value;
+                    } else if (mem.startsWith(u8, arg, "-fsoname=")) {
+                        soname = .{ .yes = arg["-fsoname=".len..] };
+                    } else if (mem.eql(u8, arg, "-fno-soname")) {
+                        soname = .no;
                     } else if (mem.eql(u8, arg, "-femit-bin")) {
                         emit_bin = .yes_default_path;
                     } else if (mem.startsWith(u8, arg, "-femit-bin=")) {
@@ -948,6 +964,7 @@ fn buildOutputType(
         },
         .cc, .cpp => {
             emit_h = .no;
+            soname = .no;
             strip = true;
             ensure_libc_on_non_freestanding = true;
             ensure_libcpp_on_non_freestanding = arg_mode == .cpp;
@@ -1091,33 +1108,33 @@ fn buildOutputType(
                     if (i >= linker_args.items.len) {
                         fatal("expected linker arg after '{}'", .{arg});
                     }
-                    const soname = linker_args.items[i];
-                    override_soname = soname;
+                    const name = linker_args.items[i];
+                    soname = .{ .yes = name };
                     // Use it as --name.
                     // Example: libsoundio.so.2
                     var prefix: usize = 0;
-                    if (mem.startsWith(u8, soname, "lib")) {
+                    if (mem.startsWith(u8, name, "lib")) {
                         prefix = 3;
                     }
-                    var end: usize = soname.len;
-                    if (mem.endsWith(u8, soname, ".so")) {
+                    var end: usize = name.len;
+                    if (mem.endsWith(u8, name, ".so")) {
                         end -= 3;
                     } else {
                         var found_digit = false;
-                        while (end > 0 and std.ascii.isDigit(soname[end - 1])) {
+                        while (end > 0 and std.ascii.isDigit(name[end - 1])) {
                             found_digit = true;
                             end -= 1;
                         }
-                        if (found_digit and end > 0 and soname[end - 1] == '.') {
+                        if (found_digit and end > 0 and name[end - 1] == '.') {
                             end -= 1;
                         } else {
-                            end = soname.len;
+                            end = name.len;
                         }
-                        if (mem.endsWith(u8, soname[prefix..end], ".so")) {
+                        if (mem.endsWith(u8, name[prefix..end], ".so")) {
                             end -= 3;
                         }
                     }
-                    provided_name = soname[prefix..end];
+                    provided_name = name[prefix..end];
                 } else if (mem.eql(u8, arg, "-rpath")) {
                     i += 1;
                     if (i >= linker_args.items.len) {
@@ -1419,6 +1436,18 @@ fn buildOutputType(
     const have_enable_cache = enable_cache orelse false;
     const optional_version = if (have_version) version else null;
 
+    const resolved_soname: ?[]const u8 = switch (soname) {
+        .yes => |explicit| explicit,
+        .no => null,
+        .yes_default_value => switch (object_format) {
+            .elf => if (have_version)
+                try std.fmt.allocPrint(arena, "lib{s}.so.{d}", .{ root_name, version.major })
+            else
+                try std.fmt.allocPrint(arena, "lib{s}.so", .{root_name}),
+            else => null,
+        },
+    };
+
     const emit_bin_loc: ?Compilation.EmitLoc = switch (emit_bin) {
         .no => null,
         .yes_default_path => Compilation.EmitLoc{
@@ -1645,7 +1674,7 @@ fn buildOutputType(
         .linker_script = linker_script,
         .version_script = version_script,
         .disable_c_depfile = disable_c_depfile,
-        .override_soname = override_soname,
+        .soname = resolved_soname,
         .linker_gc_sections = linker_gc_sections,
         .linker_allow_shlib_undefined = linker_allow_shlib_undefined,
         .linker_bind_global_refs_locally = linker_bind_global_refs_locally,