GCC compatibility: Create a Group to ignore unsupported optimization

[bubbles231]

Summary

This patch creates a group that will ignore unsupported optimizations and give the user a warning. This patch includes -finline-limit as one of those ignored flags.

[sylvestre.ledru]

include/clang/Basic/DiagnosticDriverKinds.td

122

Please add quote '%0'

test/Driver/clang_f_opts.c

162

I think we should update the test to check that the warning is displayed.

[bubbles231]

Fixed make test error and added '%0' as requested.

[rnk]

This seems like the right direction, feel free to commit with some minor fixes.

include/clang/Basic/DiagnosticDriverKinds.td

122

None of our diagnostics start with a leading capital letter, so I would try to be consistent with that.

include/clang/Driver/Options.td

92

wrap before the "

1567

this looks like a good candidate for the group, I'm sure there's more

lib/Driver/Tools.cpp

3132

needs wrapping

[bubbles231]

Thanks for the feedback. I will make those changes. I just have one
question:

this looks like a good candidate for the group, I'm sure >there's more

Should I replace all clang_ignored_f_Group?
If so can I remove that group?
If not how do I know which ones to change?

[rnk]

Not everything in clang_ignored_f_Group is an optimization flag, so no, I'd
leave the rest of them alone. I believe -ivopts is an optimization flag,
so it would be appropriate to put in this group.

[bubbles231]

Thanks for clearing that up. I will add the optimization flags in another
review.

[bubbles231]

Add tests for the warning and small fixes from comments.

[sylvestre.ledru]

Merged as commit r212805
Congratulation to Arthur for his first patch!

[bubbles231]

Thanks!

include/clang/Basic/DiagnosticDriverKinds.td

def err_drv_mg_requires_m_or_mm : Error<
   "option '-MG' requires '-M' or '-MM'">;
 def err_drv_unknown_objc_runtime : Error<
   "unknown or ill-formed Objective-C runtime '%0'">;
 def err_drv_emit_llvm_link : Error<
    "-emit-llvm cannot be used when linking">;
 def err_drv_optimization_remark_pattern : Error<
   "%0 in '%1'">;
 
+def warn_ignored_gcc_optimization : Warning<"ignoring unsupported optimization flag '%0'">,
+  InGroup<UnusedCommandLineArgument>;
 def warn_O4_is_O3 : Warning<"-O4 is equivalent to -O3">, InGroup<Deprecated>;
 def warn_drv_optimization_value : Warning<"optimization level '%0' is unsupported; using '%1%2' instead">,
   InGroup<InvalidCommandLineArgument>;
 def warn_c_kext : Warning<
   "ignoring -fapple-kext which is valid for C++ and Objective-C++ only">;
 def warn_drv_input_file_unused : Warning<
   "%0: '%1' input unused%select{ when '%3' is present|}2">,
   InGroup<UnusedCommandLineArgument>;

include/clang/Driver/Options.td

 
 // Temporary groups for clang options which we know we don't support,
 // but don't want to verbosely warn the user about.
 def clang_ignored_f_Group : OptionGroup<"<clang ignored f group>">,
   Group<f_Group>;
 def clang_ignored_m_Group : OptionGroup<"<clang ignored m group>">,
   Group<m_Group>;
 
+// Group that ignores all gcc optimizations that won't be implemented
+def clang_ignored_gcc_optimization_f_Group : OptionGroup<
+  "<clang_ignored_gcc_optimization_f_Group>">, Group<f_Group>;
+
 /////////
 // Options
 
 // The internal option ID must be a valid C++ identifier and results in a
 // clang::driver::options::OPT_XX enum constant for XX.
 //
 // We want to unambiguously be able to refer to options from the driver source
 // code, for this reason the option name is mangled into an ID. This mangling

 
 defm eliminate_unused_debug_types : BooleanFFlag<"eliminate-unused-debug-types">, Group<clang_ignored_f_Group>;
 defm float_store : BooleanFFlag<"float-store">, Group<clang_ignored_f_Group>;
 defm function_attribute_list : BooleanFFlag<"function-attribute-list">, Group<clang_ignored_f_Group>;
 defm gcse : BooleanFFlag<"gcse">, Group<clang_ignored_f_Group>;
 defm gnu : BooleanFFlag<"gnu">, Group<clang_ignored_f_Group>;
 defm ident : BooleanFFlag<"ident">, Group<clang_ignored_f_Group>;
 defm implicit_templates : BooleanFFlag<"implicit-templates">, Group<clang_ignored_f_Group>;
-defm inline_limit : BooleanFFlag<"inline-limit">, Group<clang_ignored_f_Group>;
+def finline_limit_EQ : Joined<["-"], "finline-limit=">, Group<clang_ignored_gcc_optimization_f_Group>;
+defm finline_limit : BooleanFFlag<"inline-limit">, Group<clang_ignored_gcc_optimization_f_Group>;
 defm ivopts : BooleanFFlag<"ivopts">, Group<clang_ignored_f_Group>;
 defm non_call_exceptions : BooleanFFlag<"non-call-exceptions">, Group<clang_ignored_f_Group>;
 defm permissive : BooleanFFlag<"permissive">, Group<clang_ignored_f_Group>;
 defm prefetch_loop_arrays : BooleanFFlag<"prefetch-loop-arrays">, Group<clang_ignored_f_Group>;
 defm printf : BooleanFFlag<"printf">, Group<clang_ignored_f_Group>;
 defm profile : BooleanFFlag<"profile">, Group<clang_ignored_f_Group>;
 defm profile_correction : BooleanFFlag<"profile-correction">, Group<clang_ignored_f_Group>;
 defm profile_generate_sampling : BooleanFFlag<"profile-generate-sampling">, Group<clang_ignored_f_Group>;
 defm profile_reusedist : BooleanFFlag<"profile-reusedist">, Group<clang_ignored_f_Group>;

lib/Driver/Tools.cpp

if (Arg *A = Args.getLastArg(options::OPT_O_Group)) {
     if (A->getOption().matches(options::OPT_O4)) {
       CmdArgs.push_back("-O3");
       D.Diag(diag::warn_O4_is_O3);
     } else {
       A->render(Args, CmdArgs);
     }
   }
 
+  // Warn about ignored options to clang.
+  for (arg_iterator it = Args.filtered_begin(
+       options::OPT_clang_ignored_gcc_optimization_f_Group),
+       ie = Args.filtered_end(); it != ie; ++it) {
+    D.Diag(diag::warn_ignored_gcc_optimization) << (*it)->getAsString(Args);
+  }
+
   // Don't warn about unused -flto.  This can happen when we're preprocessing or
   // precompiling.
   Args.ClaimAllArgs(options::OPT_flto);
 
   Args.AddAllArgs(CmdArgs, options::OPT_W_Group);
   if (Args.hasFlag(options::OPT_pedantic, options::OPT_no_pedantic, false))
     CmdArgs.push_back("-pedantic");
   Args.AddLastArg(CmdArgs, options::OPT_pedantic_errors);

test/Driver/clang_f_opts.c

 // RUN:     -funroll-all-loops -fno-unroll-all-loops                          \
 // RUN:     -fuse-ld=gold                                                     \
 // RUN:     -fno-builtin-foobar                                               \
 // RUN:     -fno-builtin-strcat -fno-builtin-strcpy                           \
 // RUN:     -fno-var-tracking                                                 \
 // RUN:     -fno-unsigned-char                                                \
 // RUN:     -fno-signed-char                                                  \
 // RUN:     -fstrength-reduce -fno-strength-reduce                            \
+// RUN:     -finline-limit=1000                                               \
+// RUN:     -finline-limit                                                    \
 // RUN:     %s 2>&1 | FileCheck --check-prefix=IGNORE %s
 // IGNORE-NOT: error: unknown argument
 
+// Test that the warning is displayed on these.
+// RUN: %clang -### -finline-limit=1000 %s 2>&1 | FileCheck --check-prefix=CHECK-WARNING1 %s
+// RUN: %clang -### -finline-limit %s 2>&1 | FileCheck --check-prefix=CHECK-WARNING2 %s
+// CHECK-WARNING1: ignoring unsupported optimization flag '-finline-limit=1000
+// CHECK-WARNING2: ignoring unsupported optimization flag '-finline-limit'
+
 // RUN: %clang -### -fshort-wchar -fno-short-wchar %s 2>&1 | FileCheck -check-prefix=CHECK-WCHAR1 %s
 // RUN: %clang -### -fno-short-wchar -fshort-wchar %s 2>&1 | FileCheck -check-prefix=CHECK-WCHAR2 %s
 // CHECK-WCHAR1: -fno-short-wchar
 // CHECK-WCHAR1-NOT: -fshort-wchar
 // CHECK-WCHAR2: -fshort-wchar
 // CHECK-WCHAR2-NOT: -fno-short-wchar