fix up signal-related UB reporting

2 files changed, 8 insertions, 3 deletions

diff --git a/src/signal/__signal_handler.c b/src/signal/__signal_handler.c
index ca529999..9cd9eda7 100644
--- a/src/signal/__signal_handler.c
+++ b/src/signal/__signal_handler.c
@@ -8,7 +8,13 @@ void __signal_handler(int sig)
 	if (___signal.handlers[sig] != NULL) {
 		___signal.handlers[sig](sig);
 	}
-	/* TODO: if signal is fatal, trigger UB */
+
+	/* TODO: signal number to name */
+	if (sig == SIGFPE || sig == SIGILL || sig == SIGSEGV) {
+		___signal.current = 0;
+		__undefined("Signal handler for signal %d returned", sig);
+	}
+
 	___signal.current = 0;
 }
 
diff --git a/src/signal/signal.c b/src/signal/signal.c
index 927025ee..4bd74744 100644
--- a/src/signal/signal.c
+++ b/src/signal/signal.c
@@ -17,6 +17,7 @@
 #define SA_RESTART    0x10000000
 #define SA_RESTORER   0x04000000
 
+__attribute__((noinline, target("no-sse")))
 void (*signal(int sig, void (*func)(int)))(int)
 {
 	/* signal safe iff we are resetting the current signal handler */
@@ -27,8 +28,6 @@ void (*signal(int sig, void (*func)(int)))(int)
 		return SIG_ERR;
 	}
 
-	/* TODO: install __signal_handler as a hook */
-
 	void (*prev)(int) = ___signal.handlers[sig];
 	___signal.handlers[sig] = func;