[cc1as] Change -compress-debug-sections= to use --

[MaskRay]

Summary

The double dash form is documented by GNU as, used by gcc, and accepted by llvm-mc.

[MaskRay]

If you feel strong about it, I can add back -compress-debug-sections=, but it is not used by anyone.

[MaskRay]

Sorry, I have to commit this rC360495 now to unbreak our internal builds. Not sure whether the single dash form is necessary, but rC360495 keeps it.

include/clang/Driver/CC1Options.td

 def fdebug_compilation_dir : Separate<["-"], "fdebug-compilation-dir">,
   HelpText<"The compilation directory to embed in the debug info.">;
 def dwarf_debug_flags : Separate<["-"], "dwarf-debug-flags">,
   HelpText<"The string to embed in the Dwarf debug flags record.">;
 def record_command_line : Separate<["-"], "record-command-line">,
   HelpText<"The string to embed in the .LLVM.command.line section.">;
 def compress_debug_sections : Flag<["-", "--"], "compress-debug-sections">,
     HelpText<"DWARF debug sections compression">;
-def compress_debug_sections_EQ : Joined<["-"], "compress-debug-sections=">,
+def compress_debug_sections_EQ : Joined<["--"], "compress-debug-sections=">,
     HelpText<"DWARF debug sections compression type">;
 def mno_exec_stack : Flag<["-"], "mnoexecstack">,
   HelpText<"Mark the file as not needing an executable stack">;
 def massembler_fatal_warnings : Flag<["-"], "massembler-fatal-warnings">,
   HelpText<"Make assembler warnings fatal">;
 def mrelax_relocations : Flag<["--"], "mrelax-relocations">,
     HelpText<"Use relaxable elf relocations">;
 def msave_temp_labels : Flag<["-"], "msave-temp-labels">,

lib/Driver/ToolChains/Clang.cpp

static void RenderDebugInfoCompressionArgs(const ArgList &Args,
                                            const Driver &D,
                                            const ToolChain &TC) {
   const Arg *A = Args.getLastArg(options::OPT_gz, options::OPT_gz_EQ);
   if (!A)
     return;
   if (checkDebugInfoOption(A, Args, D, TC)) {
     if (A->getOption().getID() == options::OPT_gz) {
       if (llvm::zlib::isAvailable())
-        CmdArgs.push_back("-compress-debug-sections");
+        CmdArgs.push_back("--compress-debug-sections");
       else
         D.Diag(diag::warn_debug_compression_unavailable);
       return;
     }
 
     StringRef Value = A->getValue();
     if (Value == "none") {
-      CmdArgs.push_back("-compress-debug-sections=none");
+      CmdArgs.push_back("--compress-debug-sections=none");
     } else if (Value == "zlib" || Value == "zlib-gnu") {
       if (llvm::zlib::isAvailable()) {
         CmdArgs.push_back(
-            Args.MakeArgString("-compress-debug-sections=" + Twine(Value)));
+            Args.MakeArgString("--compress-debug-sections=" + Twine(Value)));
       } else {
         D.Diag(diag::warn_debug_compression_unavailable);
       }
     } else {
       D.Diag(diag::err_drv_unsupported_option_argument)
           << A->getOption().getName() << Value;
     }
   }

lib/Driver/ToolChains/Gnu.cpp

void tools::gnutools::Assembler::ConstructJob(Compilation &C,
   llvm::Reloc::Model RelocationModel;
   unsigned PICLevel;
   bool IsPIE;
   std::tie(RelocationModel, PICLevel, IsPIE) =
       ParsePICArgs(getToolChain(), Args);
 
   if (const Arg *A = Args.getLastArg(options::OPT_gz, options::OPT_gz_EQ)) {
     if (A->getOption().getID() == options::OPT_gz) {
-      CmdArgs.push_back("-compress-debug-sections");
+      CmdArgs.push_back("--compress-debug-sections");
     } else {
       StringRef Value = A->getValue();
-      if (Value == "none") {
-        CmdArgs.push_back("-compress-debug-sections=none");
-      } else if (Value == "zlib" || Value == "zlib-gnu") {
+      if (Value == "none" || Value == "zlib" || Value == "zlib-gnu") {
         CmdArgs.push_back(
-            Args.MakeArgString("-compress-debug-sections=" + Twine(Value)));
+            Args.MakeArgString("--compress-debug-sections=" + Twine(Value)));
       } else {
         D.Diag(diag::err_drv_unsupported_option_argument)
             << A->getOption().getName() << Value;
       }
     }
   }
 
   if (getToolChain().isNoExecStackDefault()) {

test/Driver/compress-noias.c

 // CHECK-POSNEG: "--nocompress-debug-sections"
 
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -Wa,-compress-debug-sections -Wa,--compress-debug-sections -c %s 2>&1 | FileCheck -check-prefix CHECK-MULTIPLE %s
 // CHECK-MULTIPLE: "-compress-debug-sections"
 // CHECK-MULTIPLE: "--compress-debug-sections"
 
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ %s
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ %s
-// CHECK-OPT_GZ: "-compress-debug-sections"
+// CHECK-OPT_GZ: "--compress-debug-sections"
 
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=none -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_NONE %s
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=none -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_NONE %s
-// CHECK-OPT_GZ_EQ_NONE: "-compress-debug-sections=none"
+// CHECK-OPT_GZ_EQ_NONE: "--compress-debug-sections=none"
 
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=zlib -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB %s
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=zlib -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB %s
-// CHECK-OPT_GZ_EQ_ZLIB: "-compress-debug-sections=zlib"
+// CHECK-OPT_GZ_EQ_ZLIB: "--compress-debug-sections=zlib"
 
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=zlib-gnu -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB_GNU %s
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=zlib-gnu -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB_GNU %s
-// CHECK-OPT_GZ_EQ_ZLIB_GNU: "-compress-debug-sections=zlib-gnu"
+// CHECK-OPT_GZ_EQ_ZLIB_GNU: "--compress-debug-sections=zlib-gnu"
 
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=invalid -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_INVALID %s
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=invalid -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_INVALID %s
 // CHECK-OPT_GZ_EQ_INVALID: error: unsupported argument 'invalid' to option 'gz='
 

test/Driver/compress.c

 // CHECK-POSNEG: "--nocompress-debug-sections"
 
 // RUN: %clang -### -fintegrated-as -Wa,-compress-debug-sections -Wa,--compress-debug-sections -c %s 2>&1 | FileCheck -check-prefix CHECK-MULTIPLE %s
 // CHECK-MULTIPLE: "-compress-debug-sections"
 // CHECK-MULTIPLE: "--compress-debug-sections"
 
 // RUN: %clang -### -fintegrated-as -gz -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ %s
 // RUN: %clang -### -fintegrated-as -gz -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ %s
-// CHECK-OPT_GZ: "-compress-debug-sections"
+// CHECK-OPT_GZ: "--compress-debug-sections"
 
 // RUN: %clang -### -fintegrated-as -gz=none -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_NONE %s
 // RUN: %clang -### -fintegrated-as -gz=none -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_NONE %s
-// CHECK-OPT_GZ_EQ_NONE: "-compress-debug-sections=none"
+// CHECK-OPT_GZ_EQ_NONE: "--compress-debug-sections=none"
 
 // RUN: %clang -### -fintegrated-as -gz=zlib -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB %s
 // RUN: %clang -### -fintegrated-as -gz=zlib -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB %s
-// CHECK-OPT_GZ_EQ_ZLIB: "-compress-debug-sections=zlib"
+// CHECK-OPT_GZ_EQ_ZLIB: "--compress-debug-sections=zlib"
 
 // RUN: %clang -### -fintegrated-as -gz=zlib-gnu -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB_GNU %s
 // RUN: %clang -### -fintegrated-as -gz=zlib-gnu -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB_GNU %s
-// CHECK-OPT_GZ_EQ_ZLIB_GNU: "-compress-debug-sections=zlib-gnu"
+// CHECK-OPT_GZ_EQ_ZLIB_GNU: "--compress-debug-sections=zlib-gnu"
 
 // RUN: %clang -### -fintegrated-as -gz=invalid -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_INVALID %s
 // RUN: %clang -### -fintegrated-as -gz=invalid -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_INVALID %s
 // CHECK-OPT_GZ_EQ_INVALID: error: unsupported argument 'invalid' to option 'gz='