introduce --single-threaded build option

closes #1764

This adds another boolean to the test matrix; hopefully it does not
inflate the time too much.

std.event.Loop does not work with this option yet. See #1908

1 files changed, 6 insertions, 0 deletions

diff --git a/src/main.cpp b/src/main.cpp
index fd8e3db2fa..81f49089be 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -59,6 +59,7 @@ static int print_full_usage(const char *arg0) {
         "  --release-fast               build with optimizations on and safety off\n"
         "  --release-safe               build with optimizations on and safety on\n"
         "  --release-small              build with size optimizations on and safety off\n"
+        "  --single-threaded            source may assume it is only used single-threaded\n"
         "  --static                     output will be statically linked\n"
         "  --strip                      exclude debug symbols\n"
         "  --target-arch [name]         specify target architecture\n"
@@ -393,6 +394,7 @@ int main(int argc, char **argv) {
     bool no_rosegment_workaround = false;
     bool system_linker_hack = false;
     TargetSubsystem subsystem = TargetSubsystemAuto;
+    bool is_single_threaded = false;
 
     if (argc >= 2 && strcmp(argv[1], "build") == 0) {
         Buf zig_exe_path_buf = BUF_INIT;
@@ -550,6 +552,8 @@ int main(int argc, char **argv) {
                 disable_pic = true;
             } else if (strcmp(arg, "--system-linker-hack") == 0) {
                 system_linker_hack = true;
+            } else if (strcmp(arg, "--single-threaded") == 0) {
+                is_single_threaded = true;
             } else if (strcmp(arg, "--test-cmd-bin") == 0) {
                 test_exec_args.append(nullptr);
             } else if (arg[1] == 'L' && arg[2] != 0) {
@@ -816,6 +820,7 @@ int main(int argc, char **argv) {
     switch (cmd) {
     case CmdBuiltin: {
         CodeGen *g = codegen_create(nullptr, target, out_type, build_mode, get_zig_lib_dir());
+        g->is_single_threaded = is_single_threaded;
         Buf *builtin_source = codegen_generate_builtin_source(g);
         if (fwrite(buf_ptr(builtin_source), 1, buf_len(builtin_source), stdout) != buf_len(builtin_source)) {
             fprintf(stderr, "unable to write to stdout: %s\n", strerror(ferror(stdout)));
@@ -889,6 +894,7 @@ int main(int argc, char **argv) {
             codegen_set_out_name(g, buf_out_name);
             codegen_set_lib_version(g, ver_major, ver_minor, ver_patch);
             codegen_set_is_test(g, cmd == CmdTest);
+            g->is_single_threaded = is_single_threaded;
             codegen_set_linker_script(g, linker_script);
             if (each_lib_rpath)
                 codegen_set_each_lib_rpath(g, each_lib_rpath);