Issue #12060: Use sig_atomic_t type and volatile keyword in the signal module.

Patch written by Charles-François Natali.

Misc/NEWS

@@ -10,6 +10,9 @@ What's New in Python 3.1.4?
 Core and Builtins
 -----------------
 
+- Issue #12060: Use sig_atomic_t type and volatile keyword in the signal
+  module. Patch written by Charles-François Natali.
+
 - Issue #1195: Fix input() if it is interrupted by CTRL+d and then CTRL+c,
   clear the end-of-file indicator after CTRL+d.
 

Modules/signalmodule.c

@@ -78,12 +78,12 @@ static long main_thread;
 static pid_t main_pid;
 #endif
 
-static struct {
-    int tripped;
+static volatile struct {
+    sig_atomic_t tripped;
     PyObject *func;
 } Handlers[NSIG];
 
-static sig_atomic_t wakeup_fd = -1;
+static volatile sig_atomic_t wakeup_fd = -1;
 
 /* Speed up sigcheck() when none tripped */
 static volatile sig_atomic_t is_tripped = 0;