# Avoid including execinfo and calling backtrace function when execinfo.h is
# not present or supplied by system's libc
#
# Closes: https://bugs.gentoo.org/829151
--- a/source/global/management/include/G4Backtrace.hh
+++ b/source/global/management/include/G4Backtrace.hh
@@ -85,23 +85,6 @@
 #  endif
 #endif

-#if defined(G4UNIX) && !defined(WIN32)
-#  include <cxxabi.h>
-#  include <execinfo.h>
-#  include <unistd.h>
-#endif
-
-#if defined(G4LINUX)
-#  include <features.h>
-#endif
-
-#include <cfenv>
-#include <csignal>
-#include <type_traits>
-
-template <typename FuncT, typename... ArgTypes>
-using G4ResultOf_t = std::invoke_result_t<FuncT, ArgTypes...>;
-
 // compatible OS and compiler
 #if defined(G4UNIX) &&                                                         \
   (defined(__GNUC__) || defined(__clang__) || defined(_INTEL_COMPILER))
@@ -109,7 +92,9 @@ using G4ResultOf_t = std::invoke_result_t<FuncT, ArgTypes...>;
 #    define G4SIGNAL_AVAILABLE
 #  endif
 #  if !defined(G4DEMANGLE_AVAILABLE)
-#    define G4DEMANGLE_AVAILABLE
+#    if defined(G4UNIX) && defined(HAVE_EXECINFO_H)
+#       define G4DEMANGLE_AVAILABLE
+#    endif
 #  endif
 #endif

@@ -121,6 +106,25 @@ using G4ResultOf_t = std::invoke_result_t<FuncT, ArgTypes...>;
 #  endif
 #endif

+#if defined(G4UNIX) && !defined(WIN32)
+#  include <cxxabi.h>
+#if defined(HAVE_EXECINFO_H)
+#  include <execinfo.h>
+#endif
+#  include <unistd.h>
+#endif
+
+#if defined(G4LINUX)
+#  include <features.h>
+#endif
+
+#include <cfenv>
+#include <csignal>
+#include <type_traits>
+
+template <typename FuncT, typename... ArgTypes>
+using G4ResultOf_t = std::invoke_result_t<FuncT, ArgTypes...>;
+
 //----------------------------------------------------------------------------//

 inline G4String G4Demangle(const char* _str)
@@ -368,6 +372,7 @@ G4Backtrace::GetMangled(FuncT&& func)
   std::array<type, Depth> btrace;
   btrace.fill((std::is_pointer<type>::value) ? nullptr : type{});

+#if defined(G4DEMANGLE_AVAILABLE)
   // plus one for this stack-frame
   std::array<void*, Depth + Offset> buffer;
   // size of returned buffer
@@ -387,6 +392,7 @@ G4Backtrace::GetMangled(FuncT&& func)
       btrace[i] = func(bsym[i]);
     free(bsym);
   }
+#endif
   return btrace;
 }

--- a/source/global/management/sources.cmake
+++ b/source/global/management/sources.cmake
@@ -6,6 +6,14 @@ set(G4MULTITHREADED ${GEANT4_BUILD_MULTITHREADED})
 set(G4_STORE_TRAJECTORY ${GEANT4_BUILD_STORE_TRAJECTORY})
 set(G4VERBOSE ${GEANT4_BUILD_VERBOSE_CODE})

+include(CheckIncludeFile)
+
+check_include_file(execinfo.h HAVE_EXECINFO_H)
+
+if(HAVE_SYS_TYPES_H)
+	list(APPEND CMAKE_REQUIRED_DEFINITIONS -DHAVE_EXECINFO_H)
+endif()
+
 configure_file(${CMAKE_CURRENT_LIST_DIR}/include/G4GlobalConfig.hh.in
   ${CMAKE_CURRENT_BINARY_DIR}/include/G4GlobalConfig.hh)