Trap on unreachable in debug mode

src/LLVM.zig

@@ -627,6 +627,7 @@ pub const OptimizationPipelineOptions = packed struct(u64) {
         optimization_level: OptimizationLevel,
         debug_info: bool,
     };
+
     pub fn default(create: Create) OptimizationPipelineOptions {
         const pref_speed = create.optimization_level.prefers_speed();
         return .{

src/compiler.bbb

@@ -85,9 +85,8 @@ os_reserve = fn (base: u64, size: u64, protection: OS_ProtectionFlags, map: OS_M
     {
         unreachable;
     }
-    else
-    {
-    }
+
+    return address;
 }
 
 Arena = struct

src/converter.zig

@@ -5771,7 +5771,14 @@ pub noinline fn convert(arena: *Arena, options: ConvertOptions) void {
 
     var error_message: llvm.String = undefined;
     const target_machine = llvm.Target.Machine.create(.{
-        .target_options = llvm.Target.Options.default(),
+        .target_options = blk: {
+            var target_options = llvm.Target.Options.default();
+            target_options.flags0.trap_unreachable = switch (options.build_mode) {
+                .debug_none, .debug_fast, .debug_size => true,
+                else => false,
+            };
+            break :blk target_options;
+        },
         .cpu_triple = llvm.String.from_slice(llvm.global.host_triple),
         .cpu_model = llvm.String.from_slice(llvm.global.host_cpu_model),
         .cpu_features = llvm.String.from_slice(llvm.global.host_cpu_features),