std: assert we discard a uleb128 number

Author: workingjubilee

library/std/src/sys/personality/dwarf/eh.rs

@@ -83,8 +83,14 @@ pub unsafe fn find_eh_action(lsda: *const u8, context: &EHContext<'_>) -> Result
     let call_site_encoding = unsafe {
         let ttype_encoding = reader.read::<u8>();
         if ttype_encoding != DW_EH_PE_omit {
-            // Rust doesn't analyze exception types, so we don't care about the type table
-            reader.read_uleb128();
+            // discard the offset to the type table, we aren't interested
+            if ttype_encoding & 0x0F != DW_EH_PE_uleb128 {
+                rtabort!(
+                    "ttype encoding assumed to not vary based on architecture! found: {:02X}",
+                    ttype_encoding & 0xF
+                );
+            }
+            let _ = reader.read_uleb128();
         }
 
         reader.read::<u8>()