From 7fb3669edb4aa3c8313ddf8b914b86a1623e0954 Mon Sep 17 00:00:00 2001 From: David Malcolm Date: Sat, 21 Dec 2019 08:49:03 -0500 Subject: [PATCH] analyzer: fix global-sm-state issue affecting sm-signal sm-signal.cc was failing to warn about the use of an fprintf call in a signal handler when the signal handler function was non-static. The root cause was a failure to copy global sm-state within sm_state_map::clone_with_remapping as called by program_state::can_merge_with_p, which led to the exploded node for the entrypoint to the handler in the "normal" state being erroneously reused for the "in_signal_handler" state, thus losing the global state, and thus failing to warn. This patch fixes the above, so that non-equal global sm-state values prevent merger of program_state, thus requiring separate exploded nodes for the "normal" and "in signal handler" states, and thus triggering the warning for the reproducer. gcc/analyzer/ChangeLog: * program-state.cc (sm_state_map::clone_with_remapping): Copy m_global_state. (selftest::test_program_state_merging_2): New selftest. (selftest::analyzer_program_state_cc_tests): Call it. gcc/testsuite/ChangeLog: * gcc.dg/analyzer/signal-6.c: New test. --- gcc/analyzer/ChangeLog | 7 +++++++ gcc/analyzer/program-state.cc | 35 ++++++++++++++++++++++++++++++++ gcc/testsuite/ChangeLog | 4 ++++ gcc/testsuite/gcc.dg/analyzer/signal-6.c | 20 ++++++++++++++++++ 4 files changed, 66 insertions(+) create mode 100644 gcc/testsuite/gcc.dg/analyzer/signal-6.c diff --git a/gcc/analyzer/ChangeLog b/gcc/analyzer/ChangeLog index d5dd0ca..7d3b109 100644 --- a/gcc/analyzer/ChangeLog +++ b/gcc/analyzer/ChangeLog @@ -1,5 +1,12 @@ 2020-01-14 David Malcolm + * program-state.cc (sm_state_map::clone_with_remapping): Copy + m_global_state. + (selftest::test_program_state_merging_2): New selftest. + (selftest::analyzer_program_state_cc_tests): Call it. + +2020-01-14 David Malcolm + * checker-path.h (checker_path::get_checker_event): New function. (checker_path): Add DISABLE_COPY_AND_ASSIGN; make fields private. * diagnostic-manager.cc diff --git a/gcc/analyzer/program-state.cc b/gcc/analyzer/program-state.cc index c9b595e..7dbdf9d 100644 --- a/gcc/analyzer/program-state.cc +++ b/gcc/analyzer/program-state.cc @@ -84,6 +84,7 @@ sm_state_map * sm_state_map::clone_with_remapping (const one_way_svalue_id_map &id_map) const { sm_state_map *result = new sm_state_map (); + result->m_global_state = m_global_state; for (typename map_t::iterator iter = m_map.begin (); iter != m_map.end (); ++iter) @@ -1348,6 +1349,39 @@ test_program_state_merging () ASSERT_EQ (s0, merged); } +/* Verify that program_states with different global-state in an sm-state + can't be merged. */ + +static void +test_program_state_merging_2 () +{ + auto_delete_vec checkers; + checkers.safe_push (make_signal_state_machine (NULL)); + extrinsic_state ext_state (checkers); + + program_state s0 (ext_state); + { + sm_state_map *smap0 = s0.m_checker_states[0]; + const state_machine::state_t TEST_STATE_0 = 0; + smap0->set_global_state (TEST_STATE_0); + ASSERT_EQ (smap0->get_global_state (), TEST_STATE_0); + } + + program_state s1 (ext_state); + { + sm_state_map *smap1 = s1.m_checker_states[0]; + const state_machine::state_t TEST_STATE_1 = 1; + smap1->set_global_state (TEST_STATE_1); + ASSERT_EQ (smap1->get_global_state (), TEST_STATE_1); + } + + ASSERT_NE (s0, s1); + + /* They ought to not be mergeable. */ + program_state merged (ext_state); + ASSERT_FALSE (s0.can_merge_with_p (s1, ext_state, &merged)); +} + /* Run all of the selftests within this file. */ void @@ -1355,6 +1389,7 @@ analyzer_program_state_cc_tests () { test_sm_state_map (); test_program_state_merging (); + test_program_state_merging_2 (); } } // namespace selftest diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 135dae08..571b51a 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,5 +1,9 @@ 2020-01-14 David Malcolm + * gcc.dg/analyzer/signal-6.c: New test. + +2020-01-14 David Malcolm + * gcc.dg/analyzer/dot-output.c: Add test coverage for a BB with no statements. diff --git a/gcc/testsuite/gcc.dg/analyzer/signal-6.c b/gcc/testsuite/gcc.dg/analyzer/signal-6.c new file mode 100644 index 0000000..f518451 --- /dev/null +++ b/gcc/testsuite/gcc.dg/analyzer/signal-6.c @@ -0,0 +1,20 @@ +#include +#include + +extern void body_of_program(void); + +/* Example of a non-static signal handler. */ + +void handler(int signum) +{ + fprintf(stderr, "LOG: %i", signum); /* { dg-warning "call to 'fprintf' from within signal handler" } */ +} + +int main(int argc, const char *argv) +{ + signal(SIGINT, handler); /* { dg-message "registering 'handler' as signal handler" } */ + + body_of_program(); + + return 0; +} -- 2.7.4