[LLDB] Use native PDB reader by default

Author: Nerixyz

lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp

@@ -83,8 +83,8 @@ constexpr OptionEnumValueElement g_pdb_reader_enums[] = {
     {
         ePDBReaderDefault,
         "default",
-        "Use DIA PDB reader unless LLDB_USE_NATIVE_PDB_READER environment "
-        "variable is set",
+        "Use native PDB reader unless LLDB_USE_NATIVE_PDB_READER environment "
+        "is set to 0",
     },
     {
         ePDBReaderDIA,
@@ -109,16 +109,10 @@ enum {
 static const bool g_should_use_native_reader_by_default = [] {
   llvm::StringRef env_value = ::getenv("LLDB_USE_NATIVE_PDB_READER");
 
-#if !LLVM_ENABLE_DIA_SDK || !defined(_WIN32)
-  // if the environment value is unset, the native reader is requested
-  if (env_value.empty())
-    return true;
-#endif
-
-  return env_value.equals_insensitive("on") ||
-         env_value.equals_insensitive("yes") ||
-         env_value.equals_insensitive("1") ||
-         env_value.equals_insensitive("true");
+  return !env_value.equals_insensitive("off") &&
+         !env_value.equals_insensitive("no") &&
+         !env_value.equals_insensitive("0") &&
+         !env_value.equals_insensitive("false");
 }();
 
 class PluginProperties : public Properties {

lldb/test/Shell/SymbolFile/NativePDB/native-setting.cpp

@@ -8,9 +8,9 @@
 // RUN: env LLDB_USE_NATIVE_PDB_READER=0 %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV0 %s
 // RUN: env LLDB_USE_NATIVE_PDB_READER=1 %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV1 %s
 
-// RUN: env LLDB_USE_NATIVE_PDB_READER=foo %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV0 %s
-// RUN: env LLDB_USE_NATIVE_PDB_READER=42 %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV0 %s
-// RUN: env LLDB_USE_NATIVE_PDB_READER=-1 %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV0 %s
+// RUN: env LLDB_USE_NATIVE_PDB_READER=foo %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV1 %s
+// RUN: env LLDB_USE_NATIVE_PDB_READER=42 %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV1 %s
+// RUN: env LLDB_USE_NATIVE_PDB_READER=-1 %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV1 %s
 
 // RUN: env LLDB_USE_NATIVE_PDB_READER=0 %lldb \
 // RUN:     -o 'settings set plugin.symbol-file.pdb.reader dia' \

lldb/test/Shell/SymbolFile/PDB/native-setting.cpp

@@ -8,9 +8,9 @@
 // RUN: env LLDB_USE_NATIVE_PDB_READER=0 %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV0 %s
 // RUN: env LLDB_USE_NATIVE_PDB_READER=1 %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV1 %s
 
-// RUN: env LLDB_USE_NATIVE_PDB_READER=foo %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV0 %s
-// RUN: env LLDB_USE_NATIVE_PDB_READER=42 %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV0 %s
-// RUN: env LLDB_USE_NATIVE_PDB_READER=-1 %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV0 %s
+// RUN: env LLDB_USE_NATIVE_PDB_READER=foo %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV1 %s
+// RUN: env LLDB_USE_NATIVE_PDB_READER=42 %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV1 %s
+// RUN: env LLDB_USE_NATIVE_PDB_READER=-1 %lldb %t.exe -o 'target modules dump symfile' 2>&1 | FileCheck --check-prefix=ENV1 %s
 
 // RUN: env LLDB_USE_NATIVE_PDB_READER=0 %lldb \
 // RUN:     -o 'settings set plugin.symbol-file.pdb.reader dia' \
@@ -36,7 +36,7 @@
 // NO-ENV-NOT: warning:
 // NO-ENV: (lldb) target modules dump symfile
 // NO-ENV: Dumping debug symbols for 1 modules.
-// NO-ENV: SymbolFile pdb
+// NO-ENV: SymbolFile native-pdb
 
 // ENV0-NOT: warning:
 // ENV0: (lldb) target modules dump symfile

llvm/docs/ReleaseNotes.md

@@ -191,6 +191,10 @@ Changes to LLDB
 * The `show-progress` setting, which became a NOOP with the introduction of the
   statusline, now defaults to off and controls using OSC escape codes to show a
   native progress bar in supporting terminals like Ghostty and ConEmu.
+* The default PDB reader on Windows was changed from DIA to native, which uses 
+  LLVM's PDB and CodeView support. You can switch back to the DIA reader with
+  `settings set plugin.symbol-file.pdb.reader dia`. Note that support for the
+  DIA reader will be removed in future versions of LLDB.
 
 Changes to BOLT
 ---------------------------------