AFL_IGNORE_PROBLEMS + library checks and documentation

docs/Changelog.md

@@ -9,6 +9,10 @@ Want to stay in the loop on major new features? Join our mailing list by
 sending a mail to <afl-users+subscribe@googlegroups.com>.
 
 ### Version ++3.15a (dev)
+  - afl-fuzz:
+    added AFL_IGNORE_PROBLEMS plus checks to identify and abort on
+    incorrect LTO usage setups and enhanced the READMEs for better
+    information on how to deal with instrumenting libraries
   - added the very good grammar mutator "GramaTron" to the
     custom_mutators
   - added optimin, a faster and better corpus minimizer by

docs/env_variables.md

@@ -432,6 +432,10 @@ checks or alter some of the more exotic semantics of the tool:
     and RECORD:000000,cnt:000009 being the crash case.
     NOTE: This option needs to be enabled in config.h first!
 
+  - If afl-fuzz encounters an incorrect fuzzing setup during a fuzzing session
+    (not at startup), it will terminate. If you do not want this then you can
+    set `AFL_IGNORE_PROBLEMS`.
+
   - If you are Jakub, you may need `AFL_I_DONT_CARE_ABOUT_MISSING_CRASHES`.
     Others need not apply, unless they also want to disable the
     `/proc/sys/kernel/core_pattern` check.