More implementation of the C standard library.

targets/_any/stdlib/SConscript

@@ -7,6 +7,8 @@ env['CRT0_PATH'] = env.File(f'src/crt0.{env["TARGET_ARCH"]}.s').abspath
 
 stdlib_sources = Split(f'''
     src/assert.cpp
+    src/ctype.cpp
+    src/errno.cpp
     src/stdio.cpp
     src/stdlib.cpp
     src/string.cpp