Merge branch 'alexnask-bundle_compiler_rt' into master

Closes #7013
Closes #6817

1 files changed, 57 insertions, 20 deletions

diff --git a/src/Compilation.zig b/src/Compilation.zig
index a66df1db7b..b7660718de 100644
--- a/src/Compilation.zig
+++ b/src/Compilation.zig
@@ -93,6 +93,9 @@ libc_static_lib: ?CRTFile = null,
 /// Populated when we build the libcompiler_rt static library. A Job to build this is placed in the queue
 /// and resolved before calling linker.flush().
 compiler_rt_static_lib: ?CRTFile = null,
+/// Populated when we build the compiler_rt_obj object. A Job to build this is placed in the queue
+/// and resolved before calling linker.flush().
+compiler_rt_obj: ?CRTFile = null,
 
 glibc_so_files: ?glibc.BuiltSharedObjects = null,
 
@@ -164,8 +167,8 @@ const Job = union(enum) {
     libcxx: void,
     libcxxabi: void,
     libssp: void,
-    /// needed when producing a dynamic library or executable
-    libcompiler_rt: void,
+    compiler_rt_lib: void,
+    compiler_rt_obj: void,
     /// needed when not linking libc and using LLVM for code generation because it generates
     /// calls to, for example, memcpy and memset.
     zig_libc: void,
@@ -350,6 +353,7 @@ pub const InitOptions = struct {
     want_sanitize_c: ?bool = null,
     want_stack_check: ?bool = null,
     want_valgrind: ?bool = null,
+    want_compiler_rt: ?bool = null,
     use_llvm: ?bool = null,
     use_lld: ?bool = null,
     use_clang: ?bool = null,
@@ -409,6 +413,9 @@ pub fn create(gpa: *Allocator, options: InitOptions) !*Compilation {
         .Lib => is_dyn_lib,
         .Exe => true,
     };
+    const needs_c_symbols = !options.is_compiler_rt_or_libc and
+        (is_exe_or_dyn_lib or (options.target.isWasm() and options.output_mode != .Obj));
+
     const comp: *Compilation = comp: {
         // For allocations that have the same lifetime as Compilation. This arena is used only during this
         // initialization and then is freed in deinit().
@@ -585,6 +592,8 @@ pub fn create(gpa: *Allocator, options: InitOptions) !*Compilation {
             break :b options.want_valgrind orelse (options.optimize_mode == .Debug);
         };
 
+        const include_compiler_rt = options.want_compiler_rt orelse needs_c_symbols;
+
         const single_threaded = options.single_threaded or target_util.isSingleThreaded(options.target);
 
         const llvm_cpu_features: ?[*:0]const u8 = if (build_options.have_llvm and use_llvm) blk: {
@@ -821,6 +830,7 @@ pub fn create(gpa: *Allocator, options: InitOptions) !*Compilation {
             .z_defs = options.linker_z_defs,
             .stack_size_override = options.stack_size_override,
             .image_base_override = options.image_base_override,
+            .include_compiler_rt = include_compiler_rt,
             .linker_script = options.linker_script,
             .version_script = options.version_script,
             .gc_sections = options.linker_gc_sections,
@@ -967,16 +977,31 @@ pub fn create(gpa: *Allocator, options: InitOptions) !*Compilation {
             try comp.work_queue.writeItem(.libcxxabi);
         }
 
-        const needs_compiler_rt_and_c = is_exe_or_dyn_lib or
-            (comp.getTarget().isWasm() and comp.bin_file.options.output_mode != .Obj);
-        if (needs_compiler_rt_and_c and build_options.is_stage1) {
-            try comp.work_queue.writeItem(.{ .libcompiler_rt = {} });
-            // MinGW provides no libssp, use our own implementation.
-            if (comp.getTarget().isMinGW()) {
-                try comp.work_queue.writeItem(.{ .libssp = {} });
+        // The `is_stage1` condition is here only because stage2 cannot yet build compiler-rt.
+        // Once it is capable this condition should be removed.
+        if (build_options.is_stage1) {
+            if (comp.bin_file.options.include_compiler_rt) {
+                if (is_exe_or_dyn_lib) {
+                    try comp.work_queue.writeItem(.{ .compiler_rt_lib = {} });
+                } else {
+                    try comp.work_queue.writeItem(.{ .compiler_rt_obj = {} });
+                    if (comp.bin_file.options.object_format != .elf) {
+                        // For ELF we can rely on using -r to link multiple objects together into one,
+                        // but to truly support `build-obj -fcompiler-rt` will require virtually
+                        // injecting `_ = @import("compiler_rt.zig")` into the root source file of
+                        // the compilation.
+                        fatal("Embedding compiler-rt into non-ELF objects is not yet implemented.", .{});
+                    }
+                }
             }
-            if (!comp.bin_file.options.link_libc) {
-                try comp.work_queue.writeItem(.{ .zig_libc = {} });
+            if (needs_c_symbols) {
+                // MinGW provides no libssp, use our own implementation.
+                if (comp.getTarget().isMinGW()) {
+                    try comp.work_queue.writeItem(.{ .libssp = {} });
+                }
+                if (!comp.bin_file.options.link_libc) {
+                    try comp.work_queue.writeItem(.{ .zig_libc = {} });
+                }
             }
         }
     }
@@ -1374,20 +1399,26 @@ pub fn performAllTheWork(self: *Compilation) error{ TimerUnsupported, OutOfMemor
                 fatal("unable to build libcxxabi: {}", .{@errorName(err)});
             };
         },
-        .libcompiler_rt => {
-            self.buildStaticLibFromZig("compiler_rt.zig", &self.compiler_rt_static_lib) catch |err| {
+        .compiler_rt_lib => {
+            self.buildOutputFromZig("compiler_rt.zig", .Lib, &self.compiler_rt_static_lib) catch |err| {
                 // TODO Expose this as a normal compile error rather than crashing here.
-                fatal("unable to build compiler_rt: {}", .{@errorName(err)});
+                fatal("unable to build compiler_rt: {s}", .{@errorName(err)});
+            };
+        },
+        .compiler_rt_obj => {
+            self.buildOutputFromZig("compiler_rt.zig", .Obj, &self.compiler_rt_obj) catch |err| {
+                // TODO Expose this as a normal compile error rather than crashing here.
+                fatal("unable to build compiler_rt: {s}", .{@errorName(err)});
             };
         },
         .libssp => {
-            self.buildStaticLibFromZig("ssp.zig", &self.libssp_static_lib) catch |err| {
+            self.buildOutputFromZig("ssp.zig", .Lib, &self.libssp_static_lib) catch |err| {
                 // TODO Expose this as a normal compile error rather than crashing here.
                 fatal("unable to build libssp: {}", .{@errorName(err)});
             };
         },
         .zig_libc => {
-            self.buildStaticLibFromZig("c.zig", &self.libc_static_lib) catch |err| {
+            self.buildOutputFromZig("c.zig", .Lib, &self.libc_static_lib) catch |err| {
                 // TODO Expose this as a normal compile error rather than crashing here.
                 fatal("unable to build zig's multitarget libc: {}", .{@errorName(err)});
             };
@@ -2551,10 +2582,16 @@ pub fn updateSubCompilation(sub_compilation: *Compilation) !void {
     }
 }
 
-fn buildStaticLibFromZig(comp: *Compilation, src_basename: []const u8, out: *?CRTFile) !void {
+fn buildOutputFromZig(
+    comp: *Compilation,
+    src_basename: []const u8,
+    output_mode: std.builtin.OutputMode,
+    out: *?CRTFile,
+) !void {
     const tracy = trace(@src());
     defer tracy.end();
 
+    std.debug.assert(output_mode != .Exe);
     const special_sub = "std" ++ std.fs.path.sep_str ++ "special";
     const special_path = try comp.zig_lib_directory.join(comp.gpa, &[_][]const u8{special_sub});
     defer comp.gpa.free(special_path);
@@ -2571,11 +2608,11 @@ fn buildStaticLibFromZig(comp: *Compilation, src_basename: []const u8, out: *?CR
     };
     const root_name = mem.split(src_basename, ".").next().?;
     const target = comp.getTarget();
-    const output_mode: std.builtin.OutputMode = if (target.cpu.arch.isWasm()) .Obj else .Lib;
+    const fixed_output_mode = if (target.cpu.arch.isWasm()) .Obj else output_mode;
     const bin_basename = try std.zig.binNameAlloc(comp.gpa, .{
         .root_name = root_name,
         .target = target,
-        .output_mode = output_mode,
+        .output_mode = fixed_output_mode,
     });
     defer comp.gpa.free(bin_basename);
 
@@ -2598,7 +2635,7 @@ fn buildStaticLibFromZig(comp: *Compilation, src_basename: []const u8, out: *?CR
         .target = target,
         .root_name = root_name,
         .root_pkg = &root_pkg,
-        .output_mode = output_mode,
+        .output_mode = fixed_output_mode,
         .rand = comp.rand,
         .libc_installation = comp.bin_file.options.libc_installation,
         .emit_bin = emit_bin,