PR analyzer/95188 reports that diagnostics from
-Wanalyzer-unsafe-call-within-signal-handler use the wrong
source location when reporting the signal-handler registration
event in the diagnostic_path. The diagnostics erroneously use the
location of the first stmt in the basic block containing the call
to "signal", rather than that of the call itself.
Fixed thusly.
Successfully bootstrapped & regrtested on x86_64-pc-linux-gnu.
Pushed to master as r11-3537-gd60d63a00bb50ba6896939705c589578177b404d.
gcc/analyzer/ChangeLog:
PR analyzer/95188
* engine.cc (stmt_requires_new_enode_p): Split enodes before
"signal" calls.
gcc/testsuite/ChangeLog:
PR analyzer/95188
* gcc.dg/analyzer/signal-registration-loc.c: New test.
---
gcc/analyzer/engine.cc | 22 +++++++++++++-----
.../gcc.dg/analyzer/signal-registration-loc.c | 23 +++++++++++++++++++
2 files changed, 39 insertions(+), 6 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/analyzer/signal-registration-loc.c
diff --git a/gcc/analyzer/engine.cc b/gcc/analyzer/engine.cc
index c15d1195a97..0e79254ad60 100644
--- a/gcc/analyzer/engine.cc
+++ b/gcc/analyzer/engine.cc
@@ -2677,13 +2677,23 @@ static bool
stmt_requires_new_enode_p (const gimple *stmt,
const gimple *prev_stmt)
{
- /* Stop consolidating at calls to
- "__analyzer_dump_exploded_nodes", so they always appear at the
- start of an exploded_node. */
if (const gcall *call = dyn_cast <const gcall *> (stmt))
- if (is_special_named_call_p (call, "__analyzer_dump_exploded_nodes",
- 1))
- return true;
+ {
+ /* Stop consolidating at calls to
+ "__analyzer_dump_exploded_nodes", so they always appear at the
+ start of an exploded_node. */
+ if (is_special_named_call_p (call, "__analyzer_dump_exploded_nodes",
+ 1))
+ return true;
+
+ /* sm-signal.cc injects an additional custom eedge at "signal" calls
+ from the registration enode to the handler enode, separate from the
+ regular next state, which defeats the "detect state change" logic
+ in process_node. Work around this via special-casing, to ensure
+ we split the enode immediately before any "signal" call. */
+ if (is_special_named_call_p (call, "signal", 2))
+ return true;
+ }
/* If we had a PREV_STMT with an unknown location, and this stmt
has a known location, then if a state change happens here, it
diff --git a/gcc/testsuite/gcc.dg/analyzer/signal-registration-loc.c
b/gcc/testsuite/gcc.dg/analyzer/signal-registration-loc.c
new file mode 100644
index 00000000000..4bac1269b1e
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/analyzer/signal-registration-loc.c
@@ -0,0 +1,23 @@
+/* Ensure we use the correct location when reporting where the
+ signal handler was registered (PR analyzer/95188). */
+
+/* { dg-require-effective-target signal } */
+
+#include <stdio.h>
+#include <signal.h>
+
+int g;
+extern int foo (void);
+
+static void
+handler (int n)
+{
+ fprintf (stderr, "got here: %i\n", g); /* { dg-warning "call to 'fprintf'
from within signal handler" } */
+}
+
+int main (int argc, char *argv[])
+{
+ g = foo (); /* { dg-bogus "registering" } */
+ signal (SIGSEGV, handler); /* { dg-message "registering 'handler' as signal
handler" } */
+ return 0;
+}
--
2.26.2
