Closes #1215: document better why it is not a good idea to catch e.g. SIGSEGV and refer to faulthandler.
Patch by Martin Pool.
diff --git a/Doc/library/signal.rst b/Doc/library/signal.rst
index 2a472fe..84e2836 100644
--- a/Doc/library/signal.rst
+++ b/Doc/library/signal.rst
@@ -36,7 +36,11 @@
This has consequences:
* It makes little sense to catch synchronous errors like :const:`SIGFPE` or
- :const:`SIGSEGV`.
+ :const:`SIGSEGV` that are caused by an invalid operation in C code. Python
+ will return from the signal handler to the C code, which is likely to raise
+ the same signal again, causing Python to apparently hang. From Python 3.3
+ onwards, you can use the :mod:`faulthandler` module to report on synchronous
+ errors.
* A long-running calculation implemented purely in C (such as regular
expression matching on a large body of text) may run uninterrupted for an