From 4f0738fe64b92710ce771f0fb96a124517c5497d Mon Sep 17 00:00:00 2001
From: Ben Visness <bvisness@gmail.com>
Date: Sat, 23 Sep 2023 17:15:08 -0500
Subject: [PATCH] Check for Xcode command-line tools

---
 Readme.md      |  4 +++-
 scripts/dev.py | 29 ++++++++++++++++-------------
 2 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/Readme.md b/Readme.md
index 9233cd5..cc54e86 100644
--- a/Readme.md
+++ b/Readme.md
@@ -29,12 +29,14 @@ The Orca command-line tools must be installed to your system in order to use the
 
 - Windows or Mac (Linux is not yet supported)
 - [Python 3.8](https://www.python.org/) or newer (for command line tools)
-- Clang
+- Clang (version 11.0 or newer)
 	- **Windows users:** `clang` can be installed via the Visual Studio installer. Search for "C++ Clang Compiler".
 	- **Mac users:** Apple's built-in `clang` does not support WebAssembly. We recommend installing `clang` via [Homebrew](https://brew.sh/) with `brew install llvm`.
 - MSVC (Visual Studio 2022 17.5 or newer) (Windows only)
 	- This can be installed through the [Visual Studio Community](https://visualstudio.microsoft.com/) installer. Ensure that your Visual Studio installation includes "Desktop development with C++".
 	- Please note the version requirement! Orca requires C11 atomics, which were only added to MSVC in late 2022.
+- Xcode command-line tools (Mac only)
+	- These can be installed with `xcode-select --install`.
 
 ### Installation instructions
 
diff --git a/scripts/dev.py b/scripts/dev.py
index a286bf3..464165a 100644
--- a/scripts/dev.py
+++ b/scripts/dev.py
@@ -17,7 +17,7 @@ from .embed_text_files import *
 from .version import check_if_source, is_orca_source, orca_version
 
 ANGLE_VERSION = "2023-07-05"
-
+MAC_SDK_DIR = "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk"
 
 def attach_dev_commands(subparsers):
     dev_cmd = subparsers.add_parser("dev", help="Commands for building Orca itself. Must be run from within an Orca source checkout.")
@@ -168,12 +168,10 @@ def build_platform_layer_lib_win(release):
     ], check=True)
 
 def build_platform_layer_lib_mac(release):
-    sdk_dir = "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk"
-
     flags = ["-mmacos-version-min=10.15.4"]
     cflags = ["-std=c11"]
     debug_flags = ["-O3"] if release else ["-g", "-DOC_DEBUG", "-DOC_LOG_COMPILE_DEBUG"]
-    ldflags = [f"-L{sdk_dir}/usr/lib", f"-F{sdk_dir}/System/Library/Frameworks/"]
+    ldflags = [f"-L{MAC_SDK_DIR}/usr/lib", f"-F{MAC_SDK_DIR}/System/Library/Frameworks/"]
     includes = ["-Isrc", "-Isrc/util", "-Isrc/platform", "-Isrc/ext", "-Isrc/ext/angle/include"]
 
     # compile metal shader
@@ -443,19 +441,24 @@ def ensure_programs():
             msg.more("and \"C++ Clang Compiler\": https://visualstudio.microsoft.com/")
             exit(1)
 
-    try:
-        subprocess.run(["clang", "-v"], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
-    except FileNotFoundError:
-        msg = log_error("clang was not found on your system.")
-        if platform.system() == "Windows":
-            msg.more("We recommend installing clang via the Visual Studio installer.")
-        elif platform.system() == "Darwin":
+    if platform.system() == "Darwin":
+        try:
+            subprocess.run(["clang", "-v"], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
+        except FileNotFoundError:
+            msg = log_error("clang was not found on your system.")
             msg.more("Run the following to install it:")
             msg.more()
             msg.more("  brew install llvm")
             msg.more()
-        exit(1)
-    # TODO(ben): Check for xcode command line tools
+            exit(1)
+
+        if not os.path.exists(MAC_SDK_DIR):
+            msg = log_error("The Xcode command-line tools are not installed.")
+            msg.more("Run the following to install them:")
+            msg.more()
+            msg.more("  xcode-select --install")
+            msg.more()
+            exit(1)
 
 
 def ensure_angle():