[gcov] Delete CC1 option -coverage-no-function-names-in-data

rL144865 incorrectly wrote function names for GCOV_TAG_FUNCTION
(this might be part of the reasons the header says
"We emit files in a corrupt version of GCOV's "gcda" file format").

rL176173 and rL177475 realized the problem and introduced -coverage-no-function-names-in-data
to work around the issue. (However, the description is wrong.
libgcov never writes function names, even before GCC 4.2).

In reality, the linker command line has to look like:

clang --coverage -Xclang -coverage-version='407*' -Xclang -coverage-cfg-checksum -Xclang -coverage-no-function-names-in-data

Failing to pass -coverage-no-function-names-in-data can make gcov 4.7~7
either produce wrong results (for one gcov-4.9 program, I see "No executable lines")
or segfault (gcov-7).
(gcov-8 uses an incompatible format.)

This patch deletes -coverage-no-function-names-in-data and the related
function names support from libclang_rt.profile

1 files changed, 0 insertions, 2 deletions

diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 01f0673..6a358f2 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1018,8 +1018,6 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
     Opts.CoverageNotesFile =
         std::string(Args.getLastArgValue(OPT_coverage_notes_file));
     Opts.CoverageExtraChecksum = Args.hasArg(OPT_coverage_cfg_checksum);
-    Opts.CoverageNoFunctionNamesInData =
-        Args.hasArg(OPT_coverage_no_function_names_in_data);
     Opts.ProfileFilterFiles =
         std::string(Args.getLastArgValue(OPT_fprofile_filter_files_EQ));
     Opts.ProfileExcludeFiles =