fix macho loading when symbols aren't availble as expected

cle/backends/macho/binding.py

@@ -500,7 +500,11 @@ def resolve_symbol(self, solist, thumb=False, extern_object=None, **kwargs):
         if isinstance(self.symbol, (SymbolTableSymbol, BindingSymbol, DyldBoundSymbol)):
             for so in solist:
                 if self.symbol.library_base_name == so.binary_basename:
-                    [symbol] = so.get_symbol(self.symbol.name)
+                    symbols = so.get_symbol(self.symbol.name)
+                    if not symbols:
+                        log.warning("Symbol %s should have been resolved by %s but wasn't", self.symbol.name, so.binary_basename)
+                        continue
+                    (symbol,) = symbols
                     assert symbol.is_export
                     self.resolve(symbol, extern_object=extern_object)
                     log.info("Resolved %s to %s", self.symbol.name, symbol)

cle/backends/macho/macho.py

@@ -331,6 +331,10 @@ def _parse_load_commands(self, lc_offset):
                 f"Assertion triggered: {count} < {self.ncmds} or {offset - lc_offset} < {self.sizeofcmds}"
             )
 
+    @staticmethod
+    def extract_soname(path):
+        return path.split('/')[-1]
+
     @classmethod
     def is_compatible(cls, stream):
         stream.seek(0)