From Craig Silverstein: Implement --debug=files to track file opens,

and implement --verbose as a synonym.

gold/debug.h

@@ -31,10 +31,11 @@ namespace gold
 
 // The different types of debugging we support.  These are bitflags.
 
-const int DEBUG_TASK = 1;
-const int DEBUG_SCRIPT = 2;
+const int DEBUG_TASK = 0x1;
+const int DEBUG_SCRIPT = 0x2;
+const int DEBUG_FILES = 0x4;
 
-const int DEBUG_ALL = DEBUG_TASK | DEBUG_SCRIPT;
+const int DEBUG_ALL = DEBUG_TASK | DEBUG_SCRIPT | DEBUG_FILES;
 
 // Convert a debug string to the appropriate enum.
 inline int
@@ -45,6 +46,7 @@ debug_string_to_enum(const char* arg)
   {
     { "task", DEBUG_TASK },
     { "script", DEBUG_SCRIPT },
+    { "files", DEBUG_FILES },
     { "all", DEBUG_ALL }
   };
 

gold/dirsearch.cc

@@ -27,6 +27,7 @@
 #include <sys/types.h>
 #include <dirent.h>
 
+#include "debug.h"
 #include "gold-threads.h"
 #include "options.h"
 #include "workqueue.h"
@@ -235,6 +236,9 @@ Dirsearch::initialize(Workqueue* workqueue,
     }
 }
 
+// NOTE: we only log failed file-lookup attempts here.  Successfully
+// lookups will eventually get logged in File_read::open.
+
 std::string
 Dirsearch::find(const std::string& n1, const std::string& n2,
 		bool *is_in_sysroot) const
@@ -253,10 +257,20 @@ Dirsearch::find(const std::string& n1, const std::string& n2,
 	  *is_in_sysroot = p->is_in_sysroot();
 	  return p->name() + '/' + n1;
 	}
-      if (!n2.empty() && pdc->find(n2))
-	{
-	  *is_in_sysroot = p->is_in_sysroot();
-	  return p->name() + '/' + n2;
+      else
+        gold_debug(DEBUG_FILES, "Attempt to open %s/%s failed",
+                   p->name().c_str(), n1.c_str());
+
+      if (!n2.empty())
+        {
+          if (pdc->find(n2))
+            {
+              *is_in_sysroot = p->is_in_sysroot();
+              return p->name() + '/' + n2;
+            }
+          else
+            gold_debug(DEBUG_FILES, "Attempt to open %s/%s failed",
+                       p->name().c_str(), n2.c_str());
 	}
     }
 

gold/fileread.cc

@@ -30,6 +30,7 @@
 #include <sys/uio.h>
 #include "filenames.h"
 
+#include "debug.h"
 #include "parameters.h"
 #include "options.h"
 #include "dirsearch.h"
@@ -118,6 +119,8 @@ File_read::open(const Task* task, const std::string& name)
 	gold_error(_("%s: fstat failed: %s"),
 		   this->name_.c_str(), strerror(errno));
       this->size_ = s.st_size;
+      gold_debug(DEBUG_FILES, "Attempt to open %s succeeded",
+                 this->name_.c_str());
     }
 
   this->token_.add_writer(task);

gold/options.h

@@ -458,7 +458,8 @@ class General_options
               N_("Alias for -d"), NULL);
 
   DEFINE_string(debug, options::TWO_DASHES, '\0', "",
-                N_("Turn on debugging"), N_("[task,script,all][,...]"));
+                N_("Turn on debugging"),
+                N_("[all,files,script,task][,...]"));
 
   DEFINE_special(defsym, options::TWO_DASHES, '\0',
                  N_("Define a symbol"), N_("SYMBOL=EXPRESSION"));
@@ -579,6 +580,9 @@ class General_options
   DEFINE_uint64(Ttext, options::ONE_DASH, '\0', -1U,
                 N_("Set the address of the text segment"), N_("ADDRESS"));
 
+  DEFINE_bool(verbose, options::TWO_DASHES, '\0', false,
+              N_("Synonym for --debug=files"), NULL);
+
   DEFINE_special(version_script, options::TWO_DASHES, '\0',
                  N_("Read version script"), N_("FILE"));
 

gold/parameters.cc

@@ -45,6 +45,9 @@ Parameters::set_options(const General_options* options)
   // For speed, we convert the options() debug var from a string to an
   // enum (from debug.h).
   this->debug_ = debug_string_to_enum(this->options().debug());
+  // If --verbose is set, it acts as "--debug=files".
+  if (options->verbose())
+    this->debug_ |= DEBUG_FILES;
 }
 
 void

gold/parameters.h

@@ -116,7 +116,9 @@ class Parameters
   int
   debug() const
   {
-    gold_assert(this->options_valid());
+    // This can be called before the options are set up.
+    if (!this->options_valid())
+      return 0;
     return debug_;
   }