diff --git a/lib/std/Build/Step/Compile.zig b/lib/std/Build/Step/Compile.zig index efa5129d97..c66fe80478 100644 --- a/lib/std/Build/Step/Compile.zig +++ b/lib/std/Build/Step/Compile.zig @@ -1220,15 +1220,18 @@ fn make(step: *Step, prog_node: *std.Progress.Node) !void { } } - // The CLI assumes if it sees a --mod argument that it is a zig - // compilation unit. If there is no root source file, then this - // is not a zig compilation unit - it is perhaps a set of - // linker objects, or C source files instead. - // In such case, there will be only one module, so we can leave - // off the naming here. + // When the CLI sees a -M argument, it determines whether it + // implies the existence of a Zig compilation unit based on + // whether there is a root source file. If there is no root + // source file, then this is not a zig compilation unit - it is + // perhaps a set of linker objects, or C source files instead. + // Linker objects are added to the CLI globally, while C source + // files must have a module parent. if (module.root_source_file) |lp| { const src = lp.getPath2(module.owner, step); - try zig_args.appendSlice(&.{ "--mod", module_cli_name, src }); + try zig_args.append(b.fmt("-M{s}={s}", .{ module_cli_name, src })); + } else if (moduleNeedsCliArg(module)) { + try zig_args.append(b.fmt("-M{s}", .{module_cli_name})); } } } @@ -1850,3 +1853,10 @@ pub fn rootModuleTarget(c: *Compile) std.Target { // The root module is always given a target, so we know this to be non-null. return c.root_module.resolved_target.?.result; } + +fn moduleNeedsCliArg(mod: *const Module) bool { + return for (mod.link_objects.items) |o| switch (o) { + .c_source_file, .c_source_files, .assembly_file, .win32_resource_file => break true, + else => continue, + } else false; +}