The Swift compiler expects the context to remain stable between when a
module is built and loaded by a client. Usually the build system would
rebuild a module if a dependency changes, or the compiler would rebuilt
the module from a swiftinterface on a context change. However, such
changes are not always detected and in that case the compiler may crash
on an inconsistency in the context. We often see this when a clang
module is poorly modularized, the headers are modified in the SDK, or
some clang define change its API.
These are project issues that used to make the compiler crash, it
provided a poor experience and doesn't encourage the developer to fix
them by themselves. Instead, let's keep track of modularization issues
encountered during deserialization and report them as proper errors when
they trigger a fatal failure preventing compilation.
Many deserialization failures at this points are caused by archives
installed over the SDK. Let's extend the current error message with a
solution for such a case.
rdar://86280699
Rather than outputting diagnostics and to stderr, output all the extra
information added when deserialization fatally fails to the pretty stack
trace instead. Since the pretty stack trace is added to crash logs, this
should avoid the dance of requesting the compiler output
- Moves the previous "**** DESERIALIZATION FAILURE ..." output to the
last pretty stack trace line
- Removes the module and compiler version notes added to the fatal
diagnostic
- Adds a new effective compiler version line for all frontend failure.
Somewhat duplicates the line from the driver, but adds in the
effective version
- Adds a new line for the full misc version of the module that failed.
May double up with previous "While reading from ..." lines that are
added in various deserialization methods, but better to have it
twice than not at all
