fix(cc): preprocessor doesn't emit bin

.vscode/launch.json

@@ -0,0 +1,35 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "(Windows) Launch",
+            "type": "cppvsdbg",
+            "request": "launch",
+            "program": "${workspaceFolder}/build/stage3/bin/zig.exe",
+            "args": [
+                "build-lib",
+                "-fsanitize-thread",
+                "-ODebug",
+                "-target",
+                "x86_64-linux",
+                "-mcpu",
+                "baseline",
+                "-Mroot=C:/Users/qemcs/Desktop/bug1/src/root.zig",
+                "--cache-dir",
+                "C:/Users/qemcs/Desktop/bug1/.zig-cache",
+                "--global-cache-dir",
+                "C:/Users/qemcs/AppData/Local/zig",
+                "--name",
+                "bug1",
+                "-dynamic"
+            ],
+            "stopAtEntry": false,
+            "cwd": "C:/Users/qemcs/Desktop/bug1",
+            "environment": [],
+            "console": "externalTerminal"
+        }
+    ]
+}

src/main.zig

@@ -2572,6 +2572,7 @@ fn buildOutputType(
                             emit_bin = .{ .yes = p };
                             clang_preprocessor_mode = .yes;
                         } else {
+                            emit_bin = .no;
                             clang_preprocessor_mode = .stdout;
                         }
                     }