r360703 - Temporarily revert "Change -gz and -Wa, --compress-debug-sections to use gABI compression (SHF_COMPRESSED)"

[Eric Christopher via cfe-commits]

Author: echristo
Date: Tue May 14 12:40:42 2019
New Revision: 360703

URL: http://llvm.org/viewvc/llvm-project?rev=360703&view=rev
Log:
Temporarily revert "Change -gz and -Wa,--compress-debug-sections to use gABI compression (SHF_COMPRESSED)"

This affects users of older (pre 2.26) binutils in such a way that they can't necessarily
work around it as it doesn't support the compress option on the command line. Reverting
to unblock them and we can revisit whether to make this change now or fix how we want
to express the option.

This reverts commit bdb21337e6e1732c9895966449c33c408336d295/r360403.

Modified:
    cfe/trunk/docs/ReleaseNotes.rst
    cfe/trunk/lib/Frontend/CompilerInvocation.cpp
    cfe/trunk/tools/driver/cc1as_main.cpp

Modified: cfe/trunk/docs/ReleaseNotes.rst
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/docs/ReleaseNotes.rst?rev=360703&r1=360702&r2=360703&view=diff
==============================================================================
--- cfe/trunk/docs/ReleaseNotes.rst (original)
+++ cfe/trunk/docs/ReleaseNotes.rst Tue May 14 12:40:42 2019
@@ -77,10 +77,7 @@ Modified Compiler Flags
 
 - `clang -dumpversion` now returns the version of Clang itself.
 
-- On ELF, ``-gz`` now defaults to ``-gz=zlib``. It produces ``SHF_COMPRESSED``
-  style compression of debug information. GNU binutils 2.26 or newer, or lld is
-  required to link produced object files. Use ``-gz=zlib-gnu`` to get the old
-  behavior.
+- ...
 
 New Pragmas in Clang
 --------------------

Modified: cfe/trunk/lib/Frontend/CompilerInvocation.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Frontend/CompilerInvocation.cpp?rev=360703&r1=360702&r2=360703&view=diff
==============================================================================
--- cfe/trunk/lib/Frontend/CompilerInvocation.cpp (original)
+++ cfe/trunk/lib/Frontend/CompilerInvocation.cpp Tue May 14 12:40:42 2019
@@ -1052,7 +1052,8 @@ static bool ParseCodeGenArgs(CodeGenOpti
   if (const Arg *A = Args.getLastArg(OPT_compress_debug_sections,
                                      OPT_compress_debug_sections_EQ)) {
     if (A->getOption().getID() == OPT_compress_debug_sections) {
-      Opts.setCompressDebugSections(llvm::DebugCompressionType::Z);
+      // TODO: be more clever about the compression type auto-detection
+      Opts.setCompressDebugSections(llvm::DebugCompressionType::GNU);
     } else {
       auto DCT = llvm::StringSwitch<llvm::DebugCompressionType>(A->getValue())
                      .Case("none", llvm::DebugCompressionType::None)

Modified: cfe/trunk/tools/driver/cc1as_main.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/tools/driver/cc1as_main.cpp?rev=360703&r1=360702&r2=360703&view=diff
==============================================================================
--- cfe/trunk/tools/driver/cc1as_main.cpp (original)
+++ cfe/trunk/tools/driver/cc1as_main.cpp Tue May 14 12:40:42 2019
@@ -221,7 +221,8 @@ bool AssemblerInvocation::CreateFromArgs
   if (const Arg *A = Args.getLastArg(OPT_compress_debug_sections,
                                      OPT_compress_debug_sections_EQ)) {
     if (A->getOption().getID() == OPT_compress_debug_sections) {
-      Opts.CompressDebugSections = llvm::DebugCompressionType::Z;
+      // TODO: be more clever about the compression type auto-detection
+      Opts.CompressDebugSections = llvm::DebugCompressionType::GNU;
     } else {
       Opts.CompressDebugSections =
           llvm::StringSwitch<llvm::DebugCompressionType>(A->getValue())