[llvm] [DWARFLinker] Allow emission of repeated identical discriminators (PR #98255)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `libc-x86_64-debian-fullbuild-dbg` running on `libc-x86_64-debian-fullbuild` while building `llvm` at step 4 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/179/builds/1832

Here is the relevant piece of the build log for the reference:
```
Step 4 (annotate) failure: 'python ../llvm-zorg/zorg/buildbot/builders/annotated/libc-linux.py ...' (failure)
...
-- Threads enabled.
-- Doxygen disabled.
-- Ninja version: 1.11.1
-- Could NOT find OCaml (missing: OCAMLFIND OCAML_VERSION OCAML_STDLIB_PATH) 
-- Could NOT find OCaml (missing: OCAMLFIND OCAML_VERSION OCAML_STDLIB_PATH) 
-- OCaml bindings disabled.
-- LLVM default target triple: x86_64-unknown-linux-gnu
-- Building with -fPIC
-- Targeting AArch64
-- Targeting AMDGPU
-- Targeting ARM
-- Targeting AVR
-- Targeting BPF
-- Targeting Hexagon
-- Targeting Lanai
-- Targeting LoongArch
-- Targeting Mips
-- Targeting MSP430
-- Targeting NVPTX
-- Targeting PowerPC
-- Targeting RISCV
-- Targeting Sparc
-- Targeting SystemZ
-- Targeting VE
-- Targeting WebAssembly
-- Targeting X86
-- Targeting XCore
-- Integration test for newhdrgen added.
-- Setting LIBC_NAMESPACE namespace to '__llvm_libc_19_0_0_git'
-- Set COMPILER_RESOURCE_DIR to /usr/lib/llvm-14/lib/clang/14.0.6 using --print-resource-dir
-- Building libc for x86_64 on linux
-- LIBC_CONF_ENABLE_STRONG_STACK_PROTECTOR: ON
-- LIBC_CONF_KEEP_FRAME_POINTER: ON
-- LIBC_CONF_FREELIST_MALLOC_BUFFER_SIZE: 1073741824
-- LIBC_CONF_MATH_OPTIMIZATIONS: 0
-- LIBC_CONF_PRINTF_DISABLE_FIXED_POINT: OFF
-- LIBC_CONF_PRINTF_DISABLE_FLOAT: OFF
-- LIBC_CONF_PRINTF_DISABLE_INDEX_MODE: OFF
-- LIBC_CONF_PRINTF_DISABLE_WRITE_INT: OFF
-- LIBC_CONF_PRINTF_FLOAT_TO_STR_USE_MEGA_LONG_DOUBLE_TABLE: OFF
-- LIBC_CONF_RAW_MUTEX_DEFAULT_SPIN_COUNT: 100
-- LIBC_CONF_RWLOCK_DEFAULT_SPIN_COUNT: 100
-- LIBC_CONF_TIMEOUT_ENSURE_MONOTONICITY: ON
-- LIBC_CONF_SCANF_DISABLE_FLOAT: OFF
-- LIBC_CONF_SCANF_DISABLE_INDEX_MODE: OFF
-- LIBC_CONF_MEMSET_X86_USE_SOFTWARE_PREFETCHING: OFF
-- LIBC_CONF_STRING_UNSAFE_WIDE_READ: OFF
-- Writing config doc to /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-project/libc/docs/configure.rst
-- Set CPU features: AVX;AVX2;FMA;SSE2;SSE4_2
-- Compiler features available: float128
Step 5 (cmake) failure: cmake (failure)
...
-- For x86_64 builtins preferring x86_64/floatdidf.c to floatdidf.c
-- For x86_64 builtins preferring x86_64/floatdisf.c to floatdisf.c
-- For x86_64 builtins preferring x86_64/floatundidf.S to floatundidf.c
-- For x86_64 builtins preferring x86_64/floatundisf.S to floatundisf.c
-- For x86_64 builtins preferring x86_64/floatdixf.c to floatdixf.c
-- For x86_64 builtins preferring x86_64/floatundixf.S to floatundixf.c
CMake Error at /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-project/compiler-rt/lib/CMakeLists.txt:44 (add_subdirectory):
  The binary directory

    /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/build/projects/compiler-rt/lib/lsan

  is already used to build a source directory.  It cannot be used to build
  source directory

    /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-project/compiler-rt/lib/lsan

  Specify a unique binary directory name.
-- Builtin supported architectures: x86_64
-- Generated Sanitizer SUPPORTED_TOOLS list on "Linux" is "asan;lsan;hwasan;msan;tsan;ubsan"
-- sanitizer_common tests on "Linux" will run against "asan;lsan;hwasan;msan;tsan;ubsan"
-- check-nsan does nothing.
-- check-shadowcallstack does nothing.
-- Clang version: 19.0.0git
-- Registering ExampleIRTransforms as a pass plugin (static build: OFF)
-- Registering Bye as a pass plugin (static build: OFF)
-- Failed to find LLVM FileCheck
-- Google Benchmark version: v0.0.0, normalized to 0.0.0
-- Enabling additional flags: -DINCLUDE_DIRECTORIES=/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-project/third-party/benchmark/include
-- Performing Test HAVE_THREAD_SAFETY_ATTRIBUTES -- success
-- Performing Test HAVE_GNU_POSIX_REGEX -- failed to compile
-- Performing Test HAVE_POSIX_REGEX -- success
-- Performing Test HAVE_STEADY_CLOCK -- success
-- Performing Test HAVE_PTHREAD_AFFINITY -- success
-- Configuring incomplete, errors occurred!
See also "/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/build/CMakeFiles/CMakeOutput.log".
See also "/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/build/CMakeFiles/CMakeError.log".
['cmake', '../llvm-project/llvm', '-GNinja', '-DCMAKE_C_COMPILER=clang', '-DCMAKE_CXX_COMPILER=clang++', '-DCMAKE_BUILD_TYPE=Debug', '-DLLVM_ENABLE_PROJECTS=llvm;libc;clang;compiler-rt', '-DLLVM_LIBC_INCLUDE_SCUDO=ON', '-DLIBC_INCLUDE_BENCHMARKS=ON', '-DLLVM_LIBC_FULL_BUILD=ON'] exited with return code 1.
The build step threw an exception...
Traceback (most recent call last):
  File "/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/build/../llvm-zorg/zorg/buildbot/builders/annotated/libc-linux.py", line 164, in step
    yield
  File "/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/build/../llvm-zorg/zorg/buildbot/builders/annotated/libc-linux.py", line 113, in main
    run_command(['cmake', os.path.join(source_dir, 'llvm')] + cmake_args)
  File "/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/build/../llvm-zorg/zorg/buildbot/builders/annotated/libc-linux.py", line 179, in run_command
    util.report_run_cmd(cmd, cwd=directory)
  File "/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-zorg/zorg/buildbot/builders/annotated/util.py", line 49, in report_run_cmd
    subprocess.check_call(cmd, shell=shell, *args, **kwargs)
  File "/usr/lib/python3.11/subprocess.py", line 413, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['cmake', '../llvm-project/llvm', '-GNinja', '-DCMAKE_C_COMPILER=clang', '-DCMAKE_CXX_COMPILER=clang++', '-DCMAKE_BUILD_TYPE=Debug', '-DLLVM_ENABLE_PROJECTS=llvm;libc;clang;compiler-rt', '-DLLVM_LIBC_INCLUDE_SCUDO=ON', '-DLIBC_INCLUDE_BENCHMARKS=ON', '-DLLVM_LIBC_FULL_BUILD=ON']' returned non-zero exit status 1.

```

https://github.com/llvm/llvm-project/pull/98255