Err package:ghc-internal

The GHC.Err module defines the code for the wired-in error functions, which have a special type in the compiler (with "open tyvars"). We cannot define these functions in a module where they might be used (e.g., GHC.Base), because the magical wired-in type will get confused with what the typechecker figures out.
This is thrown when the user calls error. The String is the argument given to error. Historically, there was a second String for the location, but it was subsumed by the backtrace mechanisms (since base-4.22).
Deprecated: ErrorCallWithLocation has been deprecated in favour of ErrorCall (which does not have a location). Backtraces are now handled by the backtrace exception mechanisms exclusively.
C-specific Marshalling support: Handling of C "errno" error codes.
Haskell representation for errno values. The implementation is deliberately exposed, to allow users to add their own definitions of Errno values.
Routines for testing return values and raising a userError exception in case of values indicating an error state.
Throw an error when an illegal sequence is encountered
Standard IO Errors.
A description of a custom type error.
error stops execution and displays an error message.
A variant of error that does not produce a stack trace.
Construct an IOError based on the given Errno value. The optional information can be used to improve the accuracy of error messages.
Deprecated: error appends the call stack now
maskUninterruptible# k s evaluates k s such that asynchronous exceptions are deferred until after evaluation has finished. Note that the result type here isn't quite as unrestricted as the polymorphic type might suggest; see the section "RuntimeRep polymorphism in continuation-style primops" for details.
Interrupts the current wait of the I/O manager if it is currently blocked. This instructs it to re-read how much it should wait and to process any pending events.
the state during mask: asynchronous exceptions are masked, but blocking operations may still be interrupted
the state during uninterruptibleMask: asynchronous exceptions are masked, and blocking operations may not be interrupted
A class method without a definition (neither a default definition, nor a definition in the appropriate instance) was called. The String gives information about which method it was.