Controlling diagnostics

weavec and weavec-cc accept Clang-style warning flags for WeaveC’s ids:

Flag	Effect
-Wno-weavec-<id>	Disable a diagnostic whose default severity is warning (annotation-required, invalid-annotation, leak, analysis-incomplete). Refused for an error (including null-dereference, use-of-uninitialized, invalid-release, out-of-bounds and invalid-integer-operation; lower those with -Wno-error=).
-Wweavec-<id>	Re-enable it.
-Wno-error=weavec-<id>	Report an error as a warning (the migration path for a codebase that wants to build while it works through the reports).
-Werror=weavec-<id>	Report a warning as an error.
-Wno-weavec, -Wno-error=weavec, -Werror=weavec	The same for every WeaveC id (-Wno-weavec leaves the errors alone).

The soundness statement assumes default severities. weavec-cc additionally takes -fno-weavec (compile only), -fweavec-strict (--strict-externs), -fweavec-report-unannotated, -fweavec-analyze-headers, -fweavec-dump-analysis, -fweavec-exclusive-borrows (--exclusive-borrows) and -fno-weavec-link (skip the link-time whole-program step).