cleaner verbose flags and zig build prints failed command

2 files changed, 64 insertions, 14 deletions

diff --git a/std/build.zig b/std/build.zig
index 84eba6d33b..7cf2ac5987 100644
--- a/std/build.zig
+++ b/std/build.zig
@@ -33,6 +33,12 @@ pub const Builder = struct {
     available_options_map: AvailableOptionsMap,
     available_options_list: ArrayList(AvailableOption),
     verbose: bool,
+    verbose_tokenize: bool,
+    verbose_ast: bool,
+    verbose_link: bool,
+    verbose_ir: bool,
+    verbose_llvm_ir: bool,
+    verbose_cimport: bool,
     invalid_user_input: bool,
     zig_exe: []const u8,
     default_step: &Step,
@@ -88,6 +94,12 @@ pub const Builder = struct {
             .build_root = build_root,
             .cache_root = %%os.path.relative(allocator, build_root, cache_root),
             .verbose = false,
+            .verbose_tokenize = false,
+            .verbose_ast = false,
+            .verbose_link = false,
+            .verbose_ir = false,
+            .verbose_llvm_ir = false,
+            .verbose_cimport = false,
             .invalid_user_input = false,
             .allocator = allocator,
             .lib_paths = ArrayList([]const u8).init(allocator),
@@ -536,15 +548,19 @@ pub const Builder = struct {
         return self.spawnChildEnvMap(null, &self.env_map, argv);
     }
 
+    fn printCmd(cwd: ?[]const u8, argv: []const []const u8) {
+        if (cwd) |yes_cwd| %%io.stderr.print("cd {} && ", yes_cwd);
+        for (argv) |arg| {
+            %%io.stderr.print("{} ", arg);
+        }
+        %%io.stderr.printf("\n");
+    }
+
     fn spawnChildEnvMap(self: &Builder, cwd: ?[]const u8, env_map: &const BufMap,
         argv: []const []const u8) -> %void
     {
         if (self.verbose) {
-            if (cwd) |yes_cwd| %%io.stderr.print("cd {}; ", yes_cwd);
-            for (argv) |arg| {
-                %%io.stderr.print("{} ", arg);
-            }
-            %%io.stderr.printf("\n");
+            printCmd(cwd, argv);
         }
 
         const child = %%os.ChildProcess.init(argv, self.allocator);
@@ -561,12 +577,15 @@ pub const Builder = struct {
         switch (term) {
             Term.Exited => |code| {
                 if (code != 0) {
-                    %%io.stderr.printf("Process {} exited with error code {}\n", argv[0], code);
+                    %%io.stderr.printf("The following command exited with error code {}:\n", code);
+                    printCmd(cwd, argv);
                     return error.UncleanExit;
                 }
             },
             else => {
-                %%io.stderr.printf("Process {} terminated unexpectedly\n", argv[0]);
+                %%io.stderr.printf("The following command terminated unexpectedly:\n");
+                printCmd(cwd, argv);
+
                 return error.UncleanExit;
             },
         };
@@ -1117,6 +1136,12 @@ pub const LibExeObjStep = struct {
         if (self.verbose) {
             %%zig_args.append("--verbose");
         }
+        if (builder.verbose_tokenize) %%zig_args.append("--verbose-tokenize");
+        if (builder.verbose_ast) %%zig_args.append("--verbose-ast");
+        if (builder.verbose_cimport) %%zig_args.append("--verbose-cimport");
+        if (builder.verbose_ir) %%zig_args.append("--verbose-ir");
+        if (builder.verbose_llvm_ir) %%zig_args.append("--verbose-llvm-ir");
+        if (builder.verbose_link) %%zig_args.append("--verbose-link");
 
         if (self.strip) {
             %%zig_args.append("--strip");
diff --git a/std/special/build_runner.zig b/std/special/build_runner.zig
index b1fbfc6c2b..089137c923 100644
--- a/std/special/build_runner.zig
+++ b/std/special/build_runner.zig
@@ -69,6 +69,18 @@ pub fn main() -> %void {
                     %%io.stderr.printf("Expected argument after --prefix\n\n");
                     return usage(&builder, false, &io.stderr);
                 });
+            } else if (mem.eql(u8, arg, "--verbose-tokenize")) {
+                builder.verbose_tokenize = true;
+            } else if (mem.eql(u8, arg, "--verbose-ast")) {
+                builder.verbose_ast = true;
+            } else if (mem.eql(u8, arg, "--verbose-link")) {
+                builder.verbose_link = true;
+            } else if (mem.eql(u8, arg, "--verbose-ir")) {
+                builder.verbose_ir = true;
+            } else if (mem.eql(u8, arg, "--verbose-llvm-ir")) {
+                builder.verbose_llvm_ir = true;
+            } else if (mem.eql(u8, arg, "--verbose-cimport")) {
+                builder.verbose_cimport = true;
             } else {
                 %%io.stderr.printf("Unrecognized argument: {}\n\n", arg);
                 return usage(&builder, false, &io.stderr);
@@ -116,27 +128,40 @@ fn usage(builder: &Builder, already_ran_build: bool, out_stream: &io.OutStream)
         \\
         \\General Options:
         \\  --help                 Print this help and exit
-        \\  --build-file [file]    Override path to build.zig
-        \\  --cache-dir [path]     Override path to cache directory
         \\  --verbose              Print commands before executing them
-        \\  --debug-build-verbose  Print verbose debugging information for the build system itself
-        \\  --prefix [prefix]      Override default install prefix
+        \\  --prefix $path         Override default install prefix
         \\
         \\Project-Specific Options:
         \\
     );
 
     if (builder.available_options_list.len == 0) {
-        %%out_stream.printf("  (none)\n");
+        %%out_stream.print("  (none)\n");
     } else {
         for (builder.available_options_list.toSliceConst()) |option| {
             const name = %%fmt.allocPrint(allocator,
-                "  -D{}=({})", option.name, Builder.typeIdName(option.type_id));
+                "  -D{}=${}", option.name, Builder.typeIdName(option.type_id));
             defer allocator.free(name);
-            %%out_stream.printf("{s24} {}\n", name, option.description);
+            %%out_stream.print("{s24} {}\n", name, option.description);
         }
     }
 
+    %%out_stream.write(
+        \\
+        \\Advanced Options:
+        \\  --build-file $file     Override path to build.zig
+        \\  --cache-dir $path      Override path to zig cache directory
+        \\  --verbose-tokenize     Enable compiler debug output for tokenization
+        \\  --verbose-ast          Enable compiler debug output for parsing into an AST
+        \\  --verbose-link         Enable compiler debug output for linking
+        \\  --verbose-ir           Enable compiler debug output for Zig IR
+        \\  --verbose-llvm-ir      Enable compiler debug output for LLVM IR
+        \\  --verbose-cimport      Enable compiler debug output for C imports
+        \\
+    );
+
+    %%out_stream.flush();
+
     if (out_stream == &io.stderr)
         return error.InvalidArgs;
 }