Add additional debug configuration

I've added the DebugOpt config for a better debugging experience.
This version enables some optimizations and uses `_ITERATOR_DEBUG_LEVEL=0` to remove many of the slowdowns of traditional debugging while still keeping the debuggability of the app intact.
It uses the release versions of llvm and crt.

Directory.Build.props

@@ -4,6 +4,7 @@
   <PropertyGroup>
     <RootDir>$(MSBuildThisFileDirectory)</RootDir>
     <Platforms>x86;x64</Platforms>
+    <Configurations>Debug;DebugOpt;Release</Configurations>
     <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
     <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>    
     <PackageLicenseExpression>MIT</PackageLicenseExpression>

build/Helpers.lua

@@ -36,6 +36,7 @@ newoption {
   allowed = {
     { "Release",  "Release" },
     { "Debug",  "Debug" },
+    { "DebugOpt",  "DebugOpt" },
  }
 }
 
@@ -104,10 +105,15 @@ function SetupNativeProject()
 
   filter { "configurations:Debug" }
     defines { "DEBUG" }
+  
+  filter { "configurations:DebugOpt" }
+    defines { "DEBUG", "_ITERATOR_DEBUG_LEVEL=0" }
+    optimize "Debug"
+    runtime "Release"
 
   filter { "configurations:Release" }
     defines { "NDEBUG" }
-    optimize "On"
+    optimize "Full"
 
   -- Compiler-specific options
 

build/LLVM.lua

@@ -38,6 +38,18 @@ function SetupLLVMIncludes()
   local c = filter()
 
   if LLVMDirPerConfiguration then
+    filter { "configurations:DebugOpt" }
+      includedirs
+      {
+        path.join(LLVMRootDirRelease, "include"),
+        path.join(LLVMRootDirRelease, "llvm/include"),
+        path.join(LLVMRootDirRelease, "lld/include"),
+        path.join(LLVMRootDirRelease, "clang/include"),
+        path.join(LLVMRootDirRelease, "clang/lib"),
+        path.join(LLVMRootDirRelease, "build/include"),
+        path.join(LLVMRootDirRelease, "build/clang/include"),
+      }
+
     filter { "configurations:Debug" }
       includedirs
       {
@@ -121,6 +133,9 @@ function SetupLLVMLibs()
   filter {}
 
   if LLVMDirPerConfiguration then
+    filter { "configurations:DebugOpt" }
+      libdirs { path.join(LLVMRootDirRelease, "build/lib") }
+
     filter { "configurations:Debug" }
       libdirs { path.join(LLVMRootDirDebug, "build/lib") }
 
@@ -129,6 +144,9 @@ function SetupLLVMLibs()
   else
     local LLVMBuildDir = get_llvm_build_dir()
     libdirs { path.join(LLVMBuildDir, "lib") }
+      
+    filter { "configurations:DebugOpt", "toolset:msc*" }
+      libdirs { path.join(LLVMBuildDir, "RelWithDebInfo/lib") }
 
     filter { "configurations:Debug", "toolset:msc*" }
       libdirs { path.join(LLVMBuildDir, "Debug/lib") }

build/build.sh

@@ -3,7 +3,7 @@ set -e
 builddir=$(cd "$(dirname "$0")"; pwd)
 platform=x64
 vs=vs2022
-configuration=Release
+configuration=DebugOpt
 build_only=false
 ci=false
 target_framework=

build/llvm/LLVM.lua

@@ -137,6 +137,9 @@ function get_llvm_package_name(rev, conf, arch)
 end
 
 function get_llvm_configuration_name(debug)
+	if string.find(_OPTIONS["configuration"], "DebugOpt") then
+		return os.istarget("windows") and "RelWithDebInfo" or "Release"
+	end
 	if string.find(_OPTIONS["configuration"], "Debug") then
 		return "Debug"
 	end