--- a/tools/clang/lib/Driver/ToolChains/Clang.cpp	2021-06-28 16:23:38.000000000 +0000

+++ b/tools/clang/lib/Driver/ToolChains/Clang.cpp	2021-09-11 09:04:24.160000000 +0000

@@ -6264,10 +6264,10 @@

   // section, for build analysis.

   // Also record command line arguments into the debug info if

   // -grecord-gcc-switches options is set on.

-  // By default, -gno-record-gcc-switches is set on and no recording.

+  // By default, -grecord-gcc-switches is set on and the arguments are recorded.

   auto GRecordSwitches =

       Args.hasFlag(options::OPT_grecord_command_line,

-                   options::OPT_gno_record_command_line, false);

+                   options::OPT_gno_record_command_line, true);

   auto FRecordSwitches =

       Args.hasFlag(options::OPT_frecord_command_line,

                    options::OPT_fno_record_command_line, false);

--- a/tools/clang/docs/ClangCommandLineReference.rst	2021-06-28 16:23:38.000000000 +0000

+++ b/tools/clang/docs/ClangCommandLineReference.rst	2021-09-11 09:04:24.160000000 +0000

@@ -3521,6 +3521,19 @@

 .. option:: -grecord-command-line, -gno-record-command-line, -grecord-gcc-switches

+This switch causes the command-line options used to invoke the compiler driver

+to be appended to the DW_AT_producer attribute in DWARF debugging information.

+

+Unlike its GCC equivalent, it does not yet exclude compiler options that do not

+affect code generation.

+

+ALT note: '-grecord-command-line' is enabled by default in ALT, but disabled in

+upstream Clang.

+Upstream `does not really care <https://bugs.llvm.org/show_bug.cgi?id=32226>`_

+if it is enabled by default, but happened to lean the other way, unlike the GCC

+upstream. Since the option does not affect generated code (only the debug

+symbols), we believe it is not disruptive for us to use a different default.

+

 .. option:: -gsplit-dwarf

 .. program:: clang1