Don't copy static userland builds into out_rootfs_overlay by default.

I was doing that by mistake too often. To force it, use --copy-overlay.

This mechanism might also be useful for future userland content.

README.adoc

@@ -11124,7 +11124,7 @@ xdg-open bst_vs_heap_vs_hashmap.tmp.png
 
 The parameters `heap_zoom_max` and `hashmap_zoom_max` are chosen manually interactively to best showcase the regions of interest in  those plots.
 
-First we build the benchmark with <<m5ops-instructions>> enabled, and then we run it and extract the stats:
+To benchmark on gem5, we first build the benchmark with <<m5ops-instructions>> enabled, and then we run it and extract the stats:
 
 ....
 ./build-userland \

build-userland

@@ -23,17 +23,6 @@ Build our compiled userland examples.
         self._add_argument('--ccflags')
         self._add_argument('--force-rebuild')
         self._add_argument('--optimization-level')
-        self.add_argument(
-            '--out-rootfs-overlay-dir-prefix',
-            default='',
-            help='''\
-Place the output files inside the image within this additional prefix.
-This is mostly useful to place different versions of binaries with different
-build parameters inside image to compare them. See:
-* https://cirosantilli.com/linux-kernel-module-cheat#update-the-toolchain
-* https://cirosantilli.com/linux-kernel-module-cheat#out_rootfs_overlay_dir
-'''
-        )
         self.add_argument(
             'targets',
             default=[],
@@ -96,7 +85,7 @@ Default: build all examples that have their package dependencies met, e.g.:
         exit_status = self._handle_thread_pool_errors(my_thread_pool)
         if exit_status != 0:
             return exit_status
-        if not self.env['in_tree']:
+        if self.env['copy_overlay']:
             self.sh.copy_dir_if_update(
                 srcdir=build_dir,
                 destdir=os.path.join(

common.py

@@ -489,6 +489,28 @@ https://cirosantilli.com/linux-kernel-module-cheat#gem5-arm-platforms
         )
 
         # Userland.
+        self.add_argument(
+            '--copy-overlay',
+            default=True,
+            help='''\
+Copy userland build outputs to the overlay directory which will be put inside
+the image. If not given explicitly, this is disabled automatically when certain
+options are given, for example --static, since users don't usually want
+static executables to be placed in the final image, but rather only for
+user mode simulations in simulators that don't support dynamic linking like gem5.
+'''
+        )
+        self.add_argument(
+            '--out-rootfs-overlay-dir-prefix',
+            default='',
+            help='''\
+Place the output files of userland build outputs inside the image within this
+additional prefix. This is mostly useful to place different versions of binaries
+with different build parameters inside image to compare them. See:
+* https://cirosantilli.com/linux-kernel-module-cheat#update-the-toolchain
+* https://cirosantilli.com/linux-kernel-module-cheat#out_rootfs_overlay_dir
+'''
+        )
         self.add_argument(
             '--package',
             action='append',
@@ -924,6 +946,10 @@ Incompatible archs are skipped.
             env['initarg'] = 'init'
         env['quit_init'] = '{}={}'.format(env['initarg'], env['userland_quit_cmd'])
 
+        if not env['_args_given']['copy_overlay']:
+            if self.env['in_tree'] or self.env['static']:
+                env['copy_overlay'] = False
+
         # Userland
         env['userland_source_arch_arch_dir'] = join(env['userland_source_arch_dir'], env['arch'])
         if env['in_tree']: