[clang] Revert "Bump the DWARF version number to 5 on Darwin." (PR #95325)

[Florian Mayer via cfe-commits]

https://github.com/fmayer created https://github.com/llvm/llvm-project/pull/95325

Reverts llvm/llvm-project#95164

This broke a buildbot: https://lab.llvm.org/buildbot/#/builders/37/builds/35987

>From fc671bbb1ceb94f8aac63bc0e4963e5894bc660e Mon Sep 17 00:00:00 2001
From: Florian Mayer <florian.mayer at bitsrc.org>
Date: Wed, 12 Jun 2024 15:50:03 -0700
Subject: [PATCH] Revert "Bump the DWARF version number to 5 on Darwin.
 (#95164)"

This reverts commit 8f6acd973a38da6dce45faa676cbb51da37f72e5.
---
 clang/lib/Driver/ToolChains/Darwin.cpp | 12 +-----------
 clang/test/Driver/debug-options.c      | 27 +-------------------------
 2 files changed, 2 insertions(+), 37 deletions(-)

diff --git a/clang/lib/Driver/ToolChains/Darwin.cpp b/clang/lib/Driver/ToolChains/Darwin.cpp
index ca75a622b061e..ed5737915aa96 100644
--- a/clang/lib/Driver/ToolChains/Darwin.cpp
+++ b/clang/lib/Driver/ToolChains/Darwin.cpp
@@ -1257,17 +1257,7 @@ unsigned DarwinClang::GetDefaultDwarfVersion() const {
   if ((isTargetMacOSBased() && isMacosxVersionLT(10, 11)) ||
       (isTargetIOSBased() && isIPhoneOSVersionLT(9)))
     return 2;
-  // Default to use DWARF 4 on OS X 10.11 - macOS 14 / iOS 9 - iOS 17.
-  if ((isTargetMacOSBased() && isMacosxVersionLT(15)) ||
-      (isTargetIOSBased() && isIPhoneOSVersionLT(18)) ||
-      (isTargetWatchOSBased() && TargetVersion < llvm::VersionTuple(11)) ||
-      (isTargetXROS() && TargetVersion < llvm::VersionTuple(2)) ||
-      (isTargetDriverKit() && TargetVersion < llvm::VersionTuple(24)) ||
-      (isTargetMacOSBased() &&
-       TargetVersion.empty()) || // apple-darwin, no version.
-      (TargetPlatform == llvm::Triple::BridgeOS))
-    return 4;
-  return 5;
+  return 4;
 }
 
 void MachO::AddLinkRuntimeLib(const ArgList &Args, ArgStringList &CmdArgs,
diff --git a/clang/test/Driver/debug-options.c b/clang/test/Driver/debug-options.c
index 0a665f7017d63..07f6ca9e3902f 100644
--- a/clang/test/Driver/debug-options.c
+++ b/clang/test/Driver/debug-options.c
@@ -68,32 +68,7 @@
 // RUN: %clang -### -c -g %s -target x86_64-apple-driverkit19.0 2>&1 \
 // RUN:             | FileCheck -check-prefix=G_STANDALONE \
 // RUN:                         -check-prefix=G_DWARF4 %s
-// RUN: %clang -### -c -g %s -target x86_64-apple-macosx15 2>&1 \
-// RUN:             | FileCheck -check-prefix=G_STANDALONE \
-// RUN:                         -check-prefix=G_DWARF5 %s
-// RUN: %clang -### -c -g %s -target arm64-apple-ios17.0 2>&1 \
-// RUN:             | FileCheck -check-prefix=G_STANDALONE \
-// RUN:                         -check-prefix=G_DWARF4 %s
-// RUN: %clang -### -c -g %s -target arm64-apple-ios18.0 2>&1 \
-// RUN:             | FileCheck -check-prefix=G_STANDALONE \
-// RUN:                         -check-prefix=G_DWARF5 %s
-// RUN: %clang -### -c -g %s -target arm64_32-apple-watchos11 2>&1 \
-// RUN:             | FileCheck -check-prefix=G_STANDALONE \
-// RUN:                         -check-prefix=G_DWARF5 %s
-// RUN: %clang -### -c -g %s -target arm64-apple-tvos18.0 2>&1 \
-// RUN:             | FileCheck -check-prefix=G_STANDALONE \
-// RUN:                         -check-prefix=G_DWARF5 %s
-// RUN: %clang -### -c -g %s -target x86_64-apple-driverkit24.0 2>&1 \
-// RUN:             | FileCheck -check-prefix=G_STANDALONE \
-// RUN:                         -check-prefix=G_DWARF5 %s
-// RUN: %clang -### -c -g %s -target arm64-apple-xros1 2>&1 \
-// RUN:             | FileCheck -check-prefix=G_STANDALONE \
-// RUN:                         -check-prefix=G_DWARF4 %s
-// RUN: %clang -### -c -g %s -target arm64-apple-xros2 2>&1 \
-// RUN:             | FileCheck -check-prefix=G_STANDALONE \
-// RUN:                         -check-prefix=G_DWARF5 %s
-//
-// RUN: %clang -### -c -fsave-optimization-record %s    \
+// RUN: %clang -### -c -fsave-optimization-record %s \
 // RUN:        -target x86_64-apple-darwin 2>&1 \
 // RUN:             | FileCheck -check-prefix=GLTO_ONLY %s
 // RUN: %clang -### -c -g -fsave-optimization-record %s \