user: implement mlibc as the libc, finally.

It's finally done..

Signed-off-by: kaguya <vpshinomiya@protonmail.com>

user/include/mlibc/tests/rtld/rtld_next/meson.build

@@ -0,0 +1,27 @@
+# Prevent tail calls, as it breaks libc's 'calling object' detection.
+no_tail_calls = '-fno-optimize-sibling-calls'
+
+libfoo = shared_library('foo', 'libfoo.c',
+	dependencies: libc_dep,
+	c_args: no_tail_calls,
+)
+libbar = shared_library('bar', 'libbar.c',
+	dependencies: libc_dep,
+	c_args: no_tail_calls,
+)
+test_link_with = [libfoo, libbar] # foo is linked before bar
+
+libfoo_native = shared_library('native-foo', 'libfoo.c',
+	c_args: [no_tail_calls, '-D_GNU_SOURCE'],
+	link_args: '-ldl',
+	override_options: 'b_sanitize=none',
+	native: true
+)
+libbar_native = shared_library('native-bar', 'libbar.c',
+	c_args: [no_tail_calls, '-D_GNU_SOURCE'],
+	link_args: '-ldl',
+	override_options: 'b_sanitize=none',
+	native: true
+)
+test_native_link_with = [libfoo_native, libbar_native]
+