PR c++/90462 reports an ICE with -fdiagnostics-format=json when
attempting to serialize a malformed location to JSON.
The compound location_t in question has meaningful "caret" and "start"
locations, but has UNKNOWN_LOCATION for its "finish" location,
leading to a NULL pointer dereference when attempting to build a JSON
string for the filename.
This patch bulletproofs the JSON output so that attempts to write
a JSON object for a location with a NULL file will lead to an object
with no "file" key, and attempts to write a compound location with
UNKNOWN_LOCATION for its start or finish will lead to the corresponding
JSON child object being omitted.
This patch also adds a json::object::get member function, for self-testing
the above.
Successfully bootstrapped & regrtested on x86_64-pc-linux-gnu.
Committed to trunk as r271535.
gcc/ChangeLog:
PR c++/90462
* diagnostic-format-json.cc: Include "selftest.h".
(json_from_expanded_location): Only add "file" key for non-NULL
file strings.
(json_from_location_range): Don't add "start" and "finish"
children if they are UNKNOWN_LOCATION.
(selftest::test_unknown_location): New selftest.
(selftest::test_bad_endpoints): New selftest.
(selftest::diagnostic_format_json_cc_tests): New function.
* json.cc (json::object::get): New function.
(selftest::test_object_get): New selftest.
(selftest::json_cc_tests): Call it.
* json.h (json::object::get): New decl.
* selftest-run-tests.c (selftest::run_tests): Call
selftest::diagnostic_format_json_cc_tests.
* selftest.h (selftest::diagnostic_format_json_cc_tests): New
decl.
gcc/testsuite/ChangeLog:
PR c++/90462
* g++.dg/pr90462.C: New test.
---
gcc/diagnostic-format-json.cc | 60 +++++++++++++++++++++++++++++++++++++++---
gcc/json.cc | 29 ++++++++++++++++++++
gcc/json.h | 1 +
gcc/selftest-run-tests.c | 1 +
gcc/selftest.h | 1 +
gcc/testsuite/g++.dg/pr90462.C | 49 ++++++++++++++++++++++++++++++++++
6 files changed, 138 insertions(+), 3 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/pr90462.C
diff --git a/gcc/diagnostic-format-json.cc b/gcc/diagnostic-format-json.cc
index 0355210..53c3b63 100644
--- a/gcc/diagnostic-format-json.cc
+++ b/gcc/diagnostic-format-json.cc
@@ -24,6 +24,7 @@ along with GCC; see the file COPYING3. If not see
#include "coretypes.h"
#include "diagnostic.h"
#include "json.h"
+#include "selftest.h"
/* The top-level JSON array of pending diagnostics. */
@@ -45,7 +46,8 @@ json_from_expanded_location (location_t loc)
{
expanded_location exploc = expand_location (loc);
json::object *result = new json::object ();
- result->set ("file", new json::string (exploc.file));
+ if (exploc.file)
+ result->set ("file", new json::string (exploc.file));
result->set ("line", new json::number (exploc.line));
result->set ("column", new json::number (exploc.column));
return result;
@@ -66,9 +68,11 @@ json_from_location_range (const location_range *loc_range,
unsigned range_idx)
json::object *result = new json::object ();
result->set ("caret", json_from_expanded_location (caret_loc));
- if (start_loc != caret_loc)
+ if (start_loc != caret_loc
+ && start_loc != UNKNOWN_LOCATION)
result->set ("start", json_from_expanded_location (start_loc));
- if (finish_loc != caret_loc)
+ if (finish_loc != caret_loc
+ && finish_loc != UNKNOWN_LOCATION)
result->set ("finish", json_from_expanded_location (finish_loc));
if (loc_range->m_label)
@@ -262,3 +266,53 @@ diagnostic_output_format_init (diagnostic_context *context,
break;
}
}
+
+#if CHECKING_P
+
+namespace selftest {
+
+/* We shouldn't call json_from_expanded_location on UNKNOWN_LOCATION,
+ but verify that we handle this gracefully. */
+
+static void
+test_unknown_location ()
+{
+ delete json_from_expanded_location (UNKNOWN_LOCATION);
+}
+
+/* Verify that we gracefully handle attempts to serialize bad
+ compound locations. */
+
+static void
+test_bad_endpoints ()
+{
+ location_t bad_endpoints
+ = make_location (BUILTINS_LOCATION,
+ UNKNOWN_LOCATION, UNKNOWN_LOCATION);
+
+ location_range loc_range;
+ loc_range.m_loc = bad_endpoints;
+ loc_range.m_range_display_kind = SHOW_RANGE_WITH_CARET;
+ loc_range.m_label = NULL;
+
+ json::object *obj = json_from_location_range (&loc_range, 0);
+ /* We should have a "caret" value, but no "start" or "finish" values. */
+ ASSERT_TRUE (obj != NULL);
+ ASSERT_TRUE (obj->get ("caret") != NULL);
+ ASSERT_TRUE (obj->get ("start") == NULL);
+ ASSERT_TRUE (obj->get ("finish") == NULL);
+ delete obj;
+}
+
+/* Run all of the selftests within this file. */
+
+void
+diagnostic_format_json_cc_tests ()
+{
+ test_unknown_location ();
+ test_bad_endpoints ();
+}
+
+} // namespace selftest
+
+#endif /* #if CHECKING_P */
diff --git a/gcc/json.cc b/gcc/json.cc
index 2e8e21b..512e2e5 100644
--- a/gcc/json.cc
+++ b/gcc/json.cc
@@ -99,6 +99,22 @@ object::set (const char *key, value *v)
m_map.put (xstrdup (key), v);
}
+/* Get the json::value * for KEY.
+
+ The object retains ownership of the value. */
+
+value *
+object::get (const char *key) const
+{
+ gcc_assert (key);
+
+ value **ptr = const_cast <map_t &> (m_map).get (key);
+ if (ptr)
+ return *ptr;
+ else
+ return NULL;
+}
+
/* class json::array, a subclass of json::value, representing
an ordered collection of values. */
@@ -240,6 +256,18 @@ assert_print_eq (const json::value &jv, const char
*expected_json)
ASSERT_STREQ (expected_json, pp_formatted_text (&pp));
}
+/* Verify that object::get works as expected. */
+
+static void
+test_object_get ()
+{
+ object obj;
+ value *val = new json::string ("value");
+ obj.set ("foo", val);
+ ASSERT_EQ (obj.get ("foo"), val);
+ ASSERT_EQ (obj.get ("not-present"), NULL);
+}
+
/* Verify that JSON objects are written correctly. We can't test more than
one key/value pair, as we don't impose a guaranteed ordering. */
@@ -306,6 +334,7 @@ test_writing_literals ()
void
json_cc_tests ()
{
+ test_object_get ();
test_writing_objects ();
test_writing_arrays ();
test_writing_numbers ();
diff --git a/gcc/json.h b/gcc/json.h
index 0527a2fc..d8a690e 100644
--- a/gcc/json.h
+++ b/gcc/json.h
@@ -90,6 +90,7 @@ class object : public value
void print (pretty_printer *pp) const FINAL OVERRIDE;
void set (const char *key, value *v);
+ value *get (const char *key) const;
private:
typedef hash_map <char *, value *,
diff --git a/gcc/selftest-run-tests.c b/gcc/selftest-run-tests.c
index c2e0ee2..6ed7d82 100644
--- a/gcc/selftest-run-tests.c
+++ b/gcc/selftest-run-tests.c
@@ -90,6 +90,7 @@ selftest::run_tests ()
rely on. */
diagnostic_show_locus_c_tests ();
diagnostic_c_tests ();
+ diagnostic_format_json_cc_tests ();
edit_context_c_tests ();
fold_const_c_tests ();
spellcheck_c_tests ();
diff --git a/gcc/selftest.h b/gcc/selftest.h
index 3e00e75..d278f0a 100644
--- a/gcc/selftest.h
+++ b/gcc/selftest.h
@@ -218,6 +218,7 @@ extern void bitmap_c_tests ();
extern void cgraph_c_tests ();
extern void convert_c_tests ();
extern void diagnostic_c_tests ();
+extern void diagnostic_format_json_cc_tests ();
extern void diagnostic_show_locus_c_tests ();
extern void dumpfile_c_tests ();
extern void edit_context_c_tests ();
diff --git a/gcc/testsuite/g++.dg/pr90462.C b/gcc/testsuite/g++.dg/pr90462.C
new file mode 100644
index 0000000..2585ba0
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr90462.C
@@ -0,0 +1,49 @@
+/* { dg-options "-Wdeprecated-copy -fdiagnostics-format=json" } */
+
+template <class> class b;
+struct B {
+ typedef b<char> *c;
+};
+class d {
+public:
+ B::c operator->();
+};
+template <class> struct e;
+class f {
+ typedef int g;
+};
+template <class, class> class h;
+template <class i> class b {
+public:
+ i j;
+ i k;
+ int l;
+ void assign() {
+ int m;
+ h<i, int> n(&m);
+ n.o(&j, &k, l);
+ }
+};
+template <class i, class> class s : f { s &p(const i *, const i *, g); };
+template <class i, class t> s<i, t> &s<i, t>::p(const i *, const i *, g) {
+ d q;
+ q->assign();
+}
+struct G {
+ G();
+ G(int);
+ G(G &);
+};
+template <class i, class> class h {
+public:
+ h(int *);
+ void o(const i *, const i *, unsigned);
+ i r();
+};
+template <class i, class t> void h<i, t>::o(const i *, const i *, unsigned) {
+ G a;
+ a = r();
+}
+template s<char, e<char>> &s<char, e<char>>::p(const char *, const char *, g);
+
+/* { dg-regexp ".*" } */
--
1.8.5.3
