activate start code when pub main exists

and rename LinkType->LinkMode, OutType->OutputMode

lib/std/builtin.zig

@@ -350,8 +350,7 @@ pub const Endian = enum {
 
 /// This data structure is used by the Zig language code generation and
 /// therefore must be kept in sync with the compiler implementation.
-pub const OutType = enum {
-    Unknown,
+pub const OutputMode = enum {
     Exe,
     Lib,
     Obj,
@@ -359,7 +358,7 @@ pub const OutType = enum {
 
 /// This data structure is used by the Zig language code generation and
 /// therefore must be kept in sync with the compiler implementation.
-pub const LinkType = enum {
+pub const LinkMode = enum {
     Static,
     Dynamic,
 };

lib/std/special/start.zig

@@ -19,37 +19,28 @@ const is_mips = switch (builtin.arch) {
 };
 
 comptime {
-    switch (builtin.output_type) {
-        .Unknown => unreachable,
-        .Exe => {
-            if (builtin.link_libc) {
-                if (@hasDecl(root, "main") and
-                    @typeInfo(@typeOf(root.main)).Fn.calling_convention != .C)
-                {
-                    @export("main", main, .Weak);
-                }
-            } else if (builtin.os == .windows) {
-                if (!@hasDecl(root, "WinMain") and !@hasDecl(root, "WinMainCRTStartup")) {
-                    @export("WinMainCRTStartup", WinMainCRTStartup, .Strong);
-                }
-            } else if (is_wasm and builtin.os == .freestanding) {
-                if (!@hasDecl(root, "_start")) @export("_start", wasm_freestanding_start, .Strong);
-            } else if (builtin.os == .uefi) {
-                if (!@hasDecl(root, "EfiMain")) @export("EfiMain", EfiMain, .Strong);
-            } else if (is_mips) {
-                if (!@hasDecl(root, "__start")) @export("__start", _start, .Strong);
-            } else {
-                if (!@hasDecl(root, "_start")) @export("_start", _start, .Strong);
+    if (builtin.output_mode == .Lib and builtin.link_mode == .Dynamic) {
+        if (builtin.os == .windows and !@hasDecl(root, "_DllMainCRTStartup")) {
+            @export("_DllMainCRTStartup", _DllMainCRTStartup, .Strong);
+        }
+    } else if (builtin.output_mode == .Exe or @hasDecl(root, "main")) {
+        if (builtin.link_libc and @hasDecl(root, "main") and
+            @typeInfo(@typeOf(root.main)).Fn.calling_convention != .C)
+        {
+            @export("main", main, .Weak);
+        } else if (builtin.os == .windows) {
+            if (!@hasDecl(root, "WinMain") and !@hasDecl(root, "WinMainCRTStartup")) {
+                @export("WinMainCRTStartup", WinMainCRTStartup, .Strong);
             }
-        },
-        .Lib => {
-            if (builtin.os == .windows and builtin.link_type == .Dynamic and
-                !@hasDecl(root, "_DllMainCRTStartup"))
-            {
-                @export("_DllMainCRTStartup", _DllMainCRTStartup, .Strong);
-            }
-        },
-        .Obj => {},
+        } else if (is_wasm and builtin.os == .freestanding) {
+            if (!@hasDecl(root, "_start")) @export("_start", wasm_freestanding_start, .Strong);
+        } else if (builtin.os == .uefi) {
+            if (!@hasDecl(root, "EfiMain")) @export("EfiMain", EfiMain, .Strong);
+        } else if (is_mips) {
+            if (!@hasDecl(root, "__start")) @export("__start", _start, .Strong);
+        } else {
+            if (!@hasDecl(root, "_start")) @export("_start", _start, .Strong);
+        }
     }
 }
 

src/codegen.cpp

@@ -8378,8 +8378,7 @@ Buf *codegen_generate_builtin_source(CodeGen *g) {
     const char *out_type = nullptr;
     switch (g->out_type) {
         case OutTypeUnknown:
-            out_type = "Unknown";
-            break;
+            zig_unreachable();
         case OutTypeExe:
             out_type = "Exe";
             break;
@@ -8390,9 +8389,9 @@ Buf *codegen_generate_builtin_source(CodeGen *g) {
             out_type = "Obj";
             break;
     }
-    buf_appendf(contents, "pub const output_type = OutType.%s;\n", out_type);
+    buf_appendf(contents, "pub const output_mode = OutputMode.%s;\n", out_type);
     const char *link_type = g->is_dynamic ? "Dynamic" : "Static"; 
-    buf_appendf(contents, "pub const link_type = LinkType.%s;\n", link_type);
+    buf_appendf(contents, "pub const link_mode = LinkMode.%s;\n", link_type);
     buf_appendf(contents, "pub const is_test = %s;\n", bool_to_str(g->is_test_build));
     buf_appendf(contents, "pub const single_threaded = %s;\n", bool_to_str(g->is_single_threaded));
     buf_appendf(contents, "pub const os = Os.%s;\n", cur_os);

test/compile_errors.zig

@@ -156,7 +156,7 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
         "tmp.zig:9:27: error: @atomicRmw on enum only works with .Xchg",
     );
 
-    cases.addExe(
+    cases.add(
         "disallow coercion from non-null-terminated pointer to null-terminated pointer",
         \\extern fn puts(s: [*:0]const u8) c_int;
         \\pub fn main() void {
@@ -876,7 +876,7 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
         "tmp.zig:3:32: note: cast discards const qualifier",
     );
 
-    cases.addExe(
+    cases.add(
         "overflow in enum value allocation",
         \\const Moo = enum(u8) {
         \\    Last = 255,
@@ -3000,14 +3000,14 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
         "tmp.zig:3:9: error: encountered @panic at compile-time",
     );
 
-    cases.addExe(
+    cases.add(
         "wrong return type for main",
         \\pub fn main() f32 { }
     ,
         "error: expected return type of main to be 'void', '!void', 'noreturn', 'u8', or '!u8'",
     );
 
-    cases.addExe(
+    cases.add(
         "double ?? on main return value",
         \\pub fn main() ??void {
         \\}
@@ -4900,7 +4900,7 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
         "tmp.zig:3:13: error: cannot assign to constant",
     );
 
-    cases.addExe(
+    cases.add(
         "main function with bogus args type",
         \\pub fn main(args: [][]bogus) !void {}
     ,
@@ -5718,7 +5718,7 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
         "tmp.zig:4:13: error: cannot continue out of defer expression",
     );
 
-    cases.addExe(
+    cases.add(
         "calling a var args function only known at runtime",
         \\var foos = [_]fn(...) void { foo1, foo2 };
         \\
@@ -5732,7 +5732,7 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
         "tmp.zig:7:9: error: calling a generic function requires compile-time known function value",
     );
 
-    cases.addExe(
+    cases.add(
         "calling a generic function only known at runtime",
         \\var foos = [_]fn(var) void { foo1, foo2 };
         \\
@@ -6850,7 +6850,7 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
         "tmp.zig:3:23: error: vector element type must be integer, float, bool, or pointer; 'comptime_int' is invalid",
     );
 
-    cases.addExe("compileLog of tagged enum doesn't crash the compiler",
+    cases.add("compileLog of tagged enum doesn't crash the compiler",
         \\const Bar = union(enum(u32)) {
         \\    X: i32 = 1
         \\};