visit_lambda_expr list index out of range

Traceback

Traceback (most recent call last):                                                                                                                                                                                                                   
  File "/Users/tilak/.pyenv/versions/venv-3.10/bin/mypy", line 8, in <module>                                                                                                                                                                        
    sys.exit(console_entry())                                                                                                                                                                                                                        
  File "/Users/tilak/.pyenv/versions/venv-3.10/lib/python3.10/site-packages/mypy/__main__.py", line 15, in console_entry                                                                                                                             
    main()                                                                                                                                                                                                                                           
  File "mypy/main.py", line 100, in main                                                                                                                                                                                                             
  File "mypy/main.py", line 182, in run_build                                                                                                                                                                                                        
  File "mypy/build.py", line 192, in build                                                                                                                                                                                                           
  File "mypy/build.py", line 266, in _build                                                                                                                                                                                                          
  File "mypy/build.py", line 2942, in dispatch                                                                                                                                                                                                       
  File "mypy/build.py", line 3333, in process_graph                                                                                                                                                                                                  
  File "mypy/build.py", line 3414, in process_fresh_modules                                                                                                                                                                                          
  File "mypy/build.py", line 2110, in fix_cross_refs                                                                                                                                                                                                 
  File "mypy/fixup.py", line 52, in fixup_module                                                                                                                                                                                                     
  File "mypy/fixup.py", line 158, in visit_symbol_table                                                                                                                                                                                              
  File "mypy/nodes.py", line 1037, in accept                                                                                                                                                                                                         
  File "mypy/fixup.py", line 211, in visit_var                                                                                                                                                                                                       
  File "mypy/types.py", line 1435, in accept                                                                                                                                                                                                         
  File "mypy/fixup.py", line 230, in visit_instance                                                                                                                                                                                                  
  File "mypy/fixup.py", line 371, in lookup_fully_qualified_typeinfo                                                                                                                                                                                 
AssertionError: Should never get here in normal mode, got TypeAlias:threading.local instead of TypeInfo 

<path redacted>.py:-1: error: INTERNAL ERROR -- Please try using mypy master on GitHub:
https://mypy.readthedocs.io/en/stable/common_issues.html#using-a-development-mypy-build
Please report a bug at https://github.com/python/mypy/issues
version: 1.9.0
Traceback (most recent call last):
  File "mypy/checkexpr.py", line 5742, in accept
  File "mypy/nodes.py", line 2213, in accept
  File "mypy/checkexpr.py", line 5217, in visit_lambda_expr
  File "mypy/nodes.py", line 2206, in expr
IndexError: list index out of range
<redacted>.py:-1: : note: use --pdb to drop into pdb

To Reproduce

I'm unable to share the source code, but the errors above occur alternately when commenting out a type definition,
objects: list[CustomType] = [] vs. objects: list[CustomType] = [].

Your Environment

• Mypy version used: 1.9.0
• Mypy command-line flags: --install-types --non-interactive --show-traceback
• Mypy configuration options from mypy.ini (and other config files):
• Python version used: 3.10.9
• Operating system and version: MacOS Sonoma 14.4.1

Start by reading the reported traceback locations in mypy/checkexpr.py, mypy/nodes.py, mypy/fixup.py, and mypy/types.py, then try the supplied mypy 1.9.0 command if a reproducer becomes available. Done would require a minimal reproducible case and a regression test showing that the lambda expression no longer raises either internal error.