analyzer: log the stashing of named constants [PR107711]

PR analyzer/107711 seems to be a bug in how named constants are looked up
by the analyzer in the C frontend.

To help debug this, this patch extends -fdump-analyzer and
-fdump-analyzer-stderr so that they dump this part of the analyzer's
startup.

gcc/analyzer/ChangeLog:
	PR analyzer/107711
	* analyzer-language.cc: Include "diagnostic.h".
	(maybe_stash_named_constant): Add logger param and use it to log
	the name being looked up, and the result.
	(stash_named_constants): New, splitting out from...
	(on_finish_translation_unit): ...this function.  Call
	get_or_create_logfile and use the result to create a logger
	instance, passing it to stash_named_constants.
	* analyzer.h (get_or_create_any_logfile): New decl.
	* engine.cc (dump_fout, owns_dump_fout): New globals, split out
	from run_checkers.
	(get_or_create_any_logfile): New function, split out from...
	(run_checkers): ...here, so that the logfile can be opened by
	on_finish_translation_unit.  Clear the globals when closing the
	dump file.

gcc/testsuite/ChangeLog:
	PR analyzer/107711
	* gcc.dg/analyzer/fdump-analyzer-1.c: New test.

Signed-off-by: David Malcolm <dmalcolm@redhat.com>

diff --git a/gcc/analyzer/analyzer-language.cc b/gcc/analyzer/analyzer-language.cc
index 0629b681e7c1bf3500efed32842439922b05fad5..0fb43443ffddc5c12316cdbbb909f648930f7ad0 100644 (file)
--- a/gcc/analyzer/analyzer-language.cc
+++ b/gcc/analyzer/analyzer-language.cc
@@ -27,6 +27,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "analyzer/analyzer.h"
 #include "analyzer/analyzer-language.h"
 #include "analyzer/analyzer-logging.h"
+#include "diagnostic.h"
 
 /* Map from identifier to INTEGER_CST.  */
 static GTY (()) hash_map <tree, tree> *analyzer_stashed_constants;
@@ -39,8 +40,12 @@ namespace ana {
    If found, stash its value within analyzer_stashed_constants.  */
 
 static void
-maybe_stash_named_constant (const translation_unit &tu, const char *name)
+maybe_stash_named_constant (logger *logger,
+                           const translation_unit &tu,
+                           const char *name)
 {
+  LOG_FUNC_1 (logger, "name: %qs", name);
+
   if (!analyzer_stashed_constants)
     analyzer_stashed_constants = hash_map<tree, tree>::create_ggc ();
 
@@ -49,9 +54,32 @@ maybe_stash_named_constant (const translation_unit &tu, const char *name)
     {
       gcc_assert (TREE_CODE (t) == INTEGER_CST);
       analyzer_stashed_constants->put (id, t);
+      if (logger)
+       logger->log ("%qs: %qE", name, t);
+    }
+  else
+    {
+      if (logger)
+       logger->log ("%qs: not found", name);
     }
 }
 
+/* Call into TU to try to find values for the names we care about.
+   If found, stash their values within analyzer_stashed_constants.  */
+
+static void
+stash_named_constants (logger *logger, const translation_unit &tu)
+{
+  LOG_SCOPE (logger);
+
+  /* Stash named constants for use by sm-fd.cc  */
+  maybe_stash_named_constant (logger, tu, "O_ACCMODE");
+  maybe_stash_named_constant (logger, tu, "O_RDONLY");
+  maybe_stash_named_constant (logger, tu, "O_WRONLY");
+  maybe_stash_named_constant (logger, tu, "SOCK_STREAM");
+  maybe_stash_named_constant (logger, tu, "SOCK_DGRAM");
+}
+
 /* Hook for frontend to call into analyzer when TU finishes.
    This exists so that the analyzer can stash named constant values from
    header files (e.g. macros and enums) for later use when modeling the
@@ -68,12 +96,12 @@ on_finish_translation_unit (const translation_unit &tu)
   if (!flag_analyzer)
     return;
 
-  /* Stash named constants for use by sm-fd.cc  */
-  maybe_stash_named_constant (tu, "O_ACCMODE");
-  maybe_stash_named_constant (tu, "O_RDONLY");
-  maybe_stash_named_constant (tu, "O_WRONLY");
-  maybe_stash_named_constant (tu, "SOCK_STREAM");
-  maybe_stash_named_constant (tu, "SOCK_DGRAM");
+  FILE *logfile = get_or_create_any_logfile ();
+  log_user the_logger (NULL);
+  if (logfile)
+    the_logger.set_logger (new logger (logfile, 0, 0,
+                                      *global_dc->printer));
+  stash_named_constants (the_logger.get_logger (), tu);
 }
 
 /* Lookup NAME in the named constants stashed when the frontend TU finished.

diff --git a/gcc/analyzer/analyzer.h b/gcc/analyzer/analyzer.h
index 99a1d0690d5362602fb5c4badb91b2128bba7580..1b56745aba23f0b790c9356288b4ad8f3988238f 100644 (file)
--- a/gcc/analyzer/analyzer.h
+++ b/gcc/analyzer/analyzer.h
@@ -324,6 +324,8 @@ public:
 extern tree get_stashed_constant_by_name (const char *name);
 extern void log_stashed_constants (logger *logger);
 
+extern FILE *get_or_create_any_logfile ();
+
 } // namespace ana
 
 extern bool is_special_named_call_p (const gcall *call, const char *funcname,

diff --git a/gcc/analyzer/engine.cc b/gcc/analyzer/engine.cc
index fe2b9c69221fe257e0ca4e512a09a29e7d651091..b52753da7935984565b7cdc15b496a2fcdd55e19 100644 (file)
--- a/gcc/analyzer/engine.cc
+++ b/gcc/analyzer/engine.cc
@@ -6144,6 +6144,34 @@ impl_run_checkers (logger *logger)
   delete purge_map;
 }
 
+/* Handle -fdump-analyzer and -fdump-analyzer-stderr.  */
+static FILE *dump_fout = NULL;
+
+/* Track if we're responsible for closing dump_fout.  */
+static bool owns_dump_fout = false;
+
+/* If dumping is enabled, attempt to create dump_fout if it hasn't already
+   been opened.  Return it.  */
+
+FILE *
+get_or_create_any_logfile ()
+{
+  if (!dump_fout)
+    {
+      if (flag_dump_analyzer_stderr)
+       dump_fout = stderr;
+      else if (flag_dump_analyzer)
+       {
+         char *dump_filename = concat (dump_base_name, ".analyzer.txt", NULL);
+         dump_fout = fopen (dump_filename, "w");
+         free (dump_filename);
+         if (dump_fout)
+           owns_dump_fout = true;
+       }
+     }
+  return dump_fout;
+}
+
 /* External entrypoint to the analysis "engine".
    Set up any dumps, then call impl_run_checkers.  */
 
@@ -6153,23 +6181,9 @@ run_checkers ()
   /* Save input_location.  */
   location_t saved_input_location = input_location;
 
-  /* Handle -fdump-analyzer and -fdump-analyzer-stderr.  */
-  FILE *dump_fout = NULL;
-  /* Track if we're responsible for closing dump_fout.  */
-  bool owns_dump_fout = false;
-  if (flag_dump_analyzer_stderr)
-    dump_fout = stderr;
-  else if (flag_dump_analyzer)
-    {
-      char *dump_filename = concat (dump_base_name, ".analyzer.txt", NULL);
-      dump_fout = fopen (dump_filename, "w");
-      free (dump_filename);
-      if (dump_fout)
-       owns_dump_fout = true;
-    }
-
   {
     log_user the_logger (NULL);
+    get_or_create_any_logfile ();
     if (dump_fout)
       the_logger.set_logger (new logger (dump_fout, 0, 0,
                                         *global_dc->printer));
@@ -6182,7 +6196,11 @@ run_checkers ()
   }
 
   if (owns_dump_fout)
-    fclose (dump_fout);
+    {
+      fclose (dump_fout);
+      owns_dump_fout = false;
+      dump_fout = NULL;
+    }
 
   /* Restore input_location.  Subsequent passes may assume that input_location
      is some arbitrary value *not* in the block tree, which might be violated

diff --git a/gcc/testsuite/gcc.dg/analyzer/fdump-analyzer-1.c b/gcc/testsuite/gcc.dg/analyzer/fdump-analyzer-1.c
new file mode 100644 (file)
index 0000000..8962adb
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/analyzer/fdump-analyzer-1.c
@@ -0,0 +1,14 @@
+/* { dg-additional-options "-fdump-analyzer" } */
+
+void test (void)
+{
+}
+
+/* Verify that we log the named constants that we look up in the TU
+   (before the analysis pass runs).
+     { dg-final { scan-file fdump-analyzer-1.c.analyzer.txt "maybe_stash_named_constant: name: 'O_ACCMODE'" } }
+
+   Verify that we log the main part of the analysis (part of the
+   analysis pass):
+     { dg-final { scan-file fdump-analyzer-1.c.analyzer.txt "ana::run_checkers" } }
+ */