From d09378c8e852eed250902744db8353de4b78304d Mon Sep 17 00:00:00 2001
From: Jeremy Rifkin <51220084+jeremy-rifkin@users.noreply.github.com>
Date: Thu, 12 Sep 2024 23:56:09 -0500
Subject: [PATCH] Use execinfo.h by default for clang/apple clang on macos,
 #161

---
 CMakeLists.txt | 10 +++++++++-
 README.md      | 12 ++++++------
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ae26087..52a546b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -116,7 +116,15 @@ if(
   )
 )
   # Attempt to auto-config
-  if(UNIX)
+  if(APPLE AND ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang"))
+    if(HAS_EXECINFO)
+      set(CPPTRACE_UNWIND_WITH_EXECINFO On)
+      message(STATUS "Cpptrace auto config: Using execinfo.h for unwinding")
+    else()
+      set(CPPTRACE_UNWIND_WITH_NOTHING On)
+      message(FATAL_ERROR "Cpptrace auto config: No unwinding back-end seems to be supported, stack tracing will not work. To compile anyway set CPPTRACE_UNWIND_WITH_NOTHING.")
+    endif()
+  elseif(UNIX)
     if(HAS_UNWIND)
       set(CPPTRACE_UNWIND_WITH_UNWIND On)
       message(STATUS "Cpptrace auto config: Using libgcc unwind for unwinding")
diff --git a/README.md b/README.md
index b7311df..614495d 100644
--- a/README.md
+++ b/README.md
@@ -1051,12 +1051,12 @@ Unwinding, symbol resolution, and demangling.
 The library's CMake automatically configures itself for what your system supports. The ideal configuration is as
 follows:
 
-| Platform | Unwinding     | Symbols            | Demangling           |
-| -------- | ------------- | ------------------ | -------------------- |
-| Linux    | `_Unwind`     | libdwarf           | cxxabi.h             |
-| MacOS    | `_Unwind`     | libdwarf           | cxxabi.h             |
-| Windows  | `StackWalk64` | dbghelp            | No demangling needed |
-| MinGW    | `StackWalk64` | libdwarf + dbghelp | cxxabi.h             |
+| Platform | Unwinding                                               | Symbols            | Demangling           |
+| -------- | ------------------------------------------------------- | ------------------ | -------------------- |
+| Linux    | `_Unwind`                                               | libdwarf           | cxxabi.h             |
+| MacOS    | `_Unwind` for gcc, execinfo.h for clang and apple clang | libdwarf           | cxxabi.h             |
+| Windows  | `StackWalk64`                                           | dbghelp            | No demangling needed |
+| MinGW    | `StackWalk64`                                           | libdwarf + dbghelp | cxxabi.h             |
 
 Support for these back-ends is the main development focus and they should work well. If you want to use a different
 back-end such as addr2line, for example, you can configure the library to do so.