<rdar://problem/11740973>

Fixed issues that could happen when the UUID doesn't change in a binary and old stale debug info could end up being used.

llvm-svn: 160145

2 files changed, 48 insertions, 57 deletions

diff --git a/lldb/source/Core/Module.cpp b/lldb/source/Core/Module.cpp
index ee01dfe3f30..b3fac25a7c4 100644
--- a/lldb/source/Core/Module.cpp
+++ b/lldb/source/Core/Module.cpp
@@ -134,7 +134,8 @@ Module::Module (const ModuleSpec &module_spec) :
     m_did_parse_uuid (false),
     m_did_init_ast (false),
     m_is_dynamic_loader_module (false),
-    m_was_modified (false)
+    m_file_has_changed (false),
+    m_first_file_changed_log (false)
 {
     // Scope for locker below...
     {
@@ -176,7 +177,8 @@ Module::Module(const FileSpec& file_spec,
     m_did_parse_uuid (false),
     m_did_init_ast (false),
     m_is_dynamic_loader_module (false),
-    m_was_modified (false)
+    m_file_has_changed (false),
+    m_first_file_changed_log (false)
 {
     // Scope for locker below...
     {
@@ -803,32 +805,44 @@ Module::ReportError (const char *format, ...)
     }
 }
 
+bool
+Module::FileHasChanged () const
+{
+    if (m_file_has_changed == false)
+        m_file_has_changed = (m_file.GetModificationTime() != m_mod_time);
+    return m_file_has_changed;
+}
+
 void
 Module::ReportErrorIfModifyDetected (const char *format, ...)
 {
-    if (!GetModified(true) && GetModified(false))
+    if (m_first_file_changed_log == false)
     {
-        if (format)
+        if (FileHasChanged ())
         {
-            StreamString strm;
-            strm.PutCString("error: the object file ");
-            GetDescription(&strm, lldb::eDescriptionLevelFull);
-            strm.PutCString (" has been modified\n");
-            
-            va_list args;
-            va_start (args, format);
-            strm.PrintfVarArg(format, args);
-            va_end (args);
-            
-            const int format_len = strlen(format);
-            if (format_len > 0)
+            m_first_file_changed_log = true;
+            if (format)
             {
-                const char last_char = format[format_len-1];
-                if (last_char != '\n' || last_char != '\r')
-                    strm.EOL();
+                StreamString strm;
+                strm.PutCString("error: the object file ");
+                GetDescription(&strm, lldb::eDescriptionLevelFull);
+                strm.PutCString (" has been modified\n");
+                
+                va_list args;
+                va_start (args, format);
+                strm.PrintfVarArg(format, args);
+                va_end (args);
+                
+                const int format_len = strlen(format);
+                if (format_len > 0)
+                {
+                    const char last_char = format[format_len-1];
+                    if (last_char != '\n' || last_char != '\r')
+                        strm.EOL();
+                }
+                strm.PutCString("The debug session should be aborted as the original debug information has been overwritten.\n");
+                Host::SystemLog (Host::eSystemLogError, "%s", strm.GetString().c_str());
             }
-            strm.PutCString("The debug session should be aborted as the original debug information has been overwritten.\n");
-            Host::SystemLog (Host::eSystemLogError, "%s", strm.GetString().c_str());
         }
     }
 }
@@ -893,26 +907,6 @@ Module::LogMessageVerboseBacktrace (Log *log, const char *format, ...)
     }
 }
 
-bool
-Module::GetModified (bool use_cached_only)
-{
-    if (m_was_modified == false && use_cached_only == false)
-    {
-        TimeValue curr_mod_time (m_file.GetModificationTime());
-        m_was_modified = curr_mod_time != m_mod_time;
-    }
-    return m_was_modified;
-}
-
-bool
-Module::SetModified (bool b)
-{
-    const bool prev_value = m_was_modified;
-    m_was_modified = b;
-    return prev_value;
-}
-
-
 void
 Module::Dump(Stream *s)
 {
diff --git a/lldb/source/Core/ModuleList.cpp b/lldb/source/Core/ModuleList.cpp
index d6f29a6b49e..5507428c53e 100644
--- a/lldb/source/Core/ModuleList.cpp
+++ b/lldb/source/Core/ModuleList.cpp
@@ -710,24 +710,21 @@ ModuleList::GetSharedModule
             for (uint32_t module_idx = 0; module_idx < num_matching_modules; ++module_idx)
             {
                 module_sp = matching_module_list.GetModuleAtIndex(module_idx);
-                // If we had a UUID and we found a match, then that is good enough for a match
-                if (uuid_ptr)
-                    break;
-                if (module_file_spec)
+                
+                // Make sure the file for the module hasn't been modified
+                if (module_sp->FileHasChanged())
                 {
-                    // If we didn't have a UUID in mind when looking for the object file,
-                    // then we should make sure the modification time hasn't changed!
-                    TimeValue file_spec_mod_time(module_file_spec.GetModificationTime());
-                    if (file_spec_mod_time.IsValid())
-                    {
-                        if (file_spec_mod_time == module_sp->GetModificationTime())
-                            return error;
-                    }
+                    if (old_module_sp_ptr && !old_module_sp_ptr->get())
+                        *old_module_sp_ptr = module_sp;
+                    shared_module_list.Remove (module_sp);
+                    module_sp.reset();
+                }
+                else
+                {
+                    // The module matches and the module was not modified from
+                    // when it was last loaded.
+                    return error;
                 }
-                if (old_module_sp_ptr && !old_module_sp_ptr->get())
-                    *old_module_sp_ptr = module_sp;
-                shared_module_list.Remove (module_sp);
-                module_sp.reset();
             }
         }
     }