[PATCH 03/17] diff3: suppress -fanalyzer alarms

[Paul Eggert]

* src/diff3.c: Add pragma to suppress -Wanalyzer-null-dereference
alarms.

* src/diff.h (find_dir_file_pathname): Add malloc-related
attributes, to pacify gcc -Wsuggest-attribute=malloc.
---
 src/diff.h  | 12 +++++++++---
 src/diff3.c |  8 ++++++++
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/src/diff.h b/src/diff.h
index 27362c0..c469371 100644
--- a/src/diff.h
+++ b/src/diff.h
@@ -355,7 +355,9 @@ extern void print_context_script (struct change *, bool);
 extern int diff_dirs (struct comparison const *,
                       int (*) (struct comparison const *,
                                char const *, char const *));
-extern char *find_dir_file_pathname (char const *, char const *);
+extern char *find_dir_file_pathname (char const *, char const *)
+  _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_DEALLOC_FREE
+  _GL_ATTRIBUTE_RETURNS_NONNULL;
 
 /* ed.c */
 extern void print_ed_script (struct change *);
@@ -380,12 +382,16 @@ extern void print_sdiff_script (struct change *);
 /* util.c */
 extern char const change_letter[4];
 extern char const pr_program[];
-extern char *concat (char const *, char const *, char const *);
+extern char *concat (char const *, char const *, char const *)
+  _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_DEALLOC_FREE
+  _GL_ATTRIBUTE_RETURNS_NONNULL;
 extern bool lines_differ (char const *, char const *) _GL_ATTRIBUTE_PURE;
 extern lin translate_line_number (struct file_data const *, lin);
 extern struct change *find_change (struct change *);
 extern struct change *find_reverse_change (struct change *);
-extern void *zalloc (size_t);
+extern void *zalloc (size_t)
+  _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_DEALLOC_FREE
+  _GL_ATTRIBUTE_ALLOC_SIZE ((1)) _GL_ATTRIBUTE_RETURNS_NONNULL;
 extern enum changes analyze_hunk (struct change *, lin *, lin *, lin *, lin *);
 extern void begin_output (void);
 extern void debug_script (struct change *);
diff --git a/src/diff3.c b/src/diff3.c
index 6be7e3c..1f656b6 100644
--- a/src/diff3.c
+++ b/src/diff3.c
@@ -16,6 +16,14 @@
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
+/* As of GCC 11.2.1, gcc -Wanalyzer-too-complex reports that this
+   program's code is too complicated for gcc -fanalyzer.
+   FIXME: Compile with -DANALYZER_NULL_DEFERENCE and see whether the
+   resulting diagnostics are false alarms.  */
+#if 10 <= __GNUC__ && !ANALYZER_NULL_DEREFERENCE
+# pragma GCC diagnostic ignored "-Wanalyzer-null-dereference"
+#endif
+
 #include "system.h"
 #include "paths.h"
 
-- 
2.31.1