Support gcc 4.8.5, resolves #220

.github/workflows/ci.yml

@@ -25,26 +25,6 @@ jobs:
     - name: build and test
       run: |
            python3 ci/test-all-configs.py --${{matrix.compiler}} --default-config
-  test-linux-arm:
-    runs-on: ubuntu-22.04-arm
-    strategy:
-      fail-fast: false
-      matrix:
-        compiler: [gcc, clang]
-        shared: [--shared, ""]
-    steps:
-    - uses: actions/checkout@v4
-    - name: dependencies
-      run: |
-            sudo apt install gcc-10 g++-10 libgcc-10-dev libunwind8-dev
-            pip3 install colorama
-    - name: libdwarf
-      run: |
-            cd ..
-            cpptrace/ci/setup-prerequisites.sh
-    - name: build and test
-      run: |
-            python3 ci/test-all-configs.py --${{matrix.compiler}} --default-config
   test-macos:
     runs-on: macos-14
     strategy:
@@ -582,32 +562,6 @@ jobs:
     - name: test opt
       run: |
            bazel test //... -c opt
-  unittest-linux-arm:
-    runs-on: ubuntu-24.04-arm
-    strategy:
-      fail-fast: false
-      matrix:
-        compiler: [g++-10, clang++-18]
-        stdlib: [libstdc++, libc++]
-        dwarf_version: [4, 5]
-        split_dwarf: [OFF, ON]
-        exclude:
-          - compiler: g++-10
-            stdlib: libc++
-    steps:
-    - uses: actions/checkout@v4
-    - name: dependencies
-      run: |
-            sudo apt install gcc-10 g++-10 libgcc-10-dev ninja-build libc++-dev
-            cd ..
-            cpptrace/ci/setup-prerequisites-unittest.sh
-    - name: build and test
-      run: |
-            python3 ci/unittest.py \
-            --slice=compiler:${{matrix.compiler}} \
-            --slice=stdlib:${{matrix.stdlib}} \
-            --slice=dwarf_version:${{matrix.dwarf_version}} \
-            --slice=split_dwarf:${{matrix.split_dwarf}}
   unittest-macos:
     runs-on: macos-14
     steps:

CMakeLists.txt

@@ -34,12 +34,20 @@ endif()
 if(PROJECT_IS_TOP_LEVEL)
   if(CMAKE_GENERATOR STREQUAL "Ninja")
     if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
-      SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fdiagnostics-color=always")
+      include(CheckCXXCompilerFlag)
+      check_cxx_compiler_flag(-fdiagnostics-color=always HAS_CXX_FDIAGNOSTICS_COLOR)
+      if(HAS_CXX_FDIAGNOSTICS_COLOR)
+        SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fdiagnostics-color=always")
+      endif()
     elseif("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
       SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fcolor-diagnostics")
     endif()
     if("${CMAKE_C_COMPILER_ID}" STREQUAL "GNU")
-      SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fdiagnostics-color=always")
+      include(CheckCCompilerFlag)
+      check_c_compiler_flag(-fdiagnostics-color=always HAS_C_FDIAGNOSTICS_COLOR)
+      if(HAS_C_FDIAGNOSTICS_COLOR)
+        SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fdiagnostics-color=always")
+      endif()
     elseif("${CMAKE_C_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
       SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fcolor-diagnostics")
     endif()
@@ -176,6 +184,11 @@ target_compile_options(
   ${warning_options}
 )
 
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 6.0)
+  # https://godbolt.org/z/qYh89E6rq
+  target_compile_options(${target_name} PRIVATE -Wno-missing-field-initializers)
+endif()
+
 set(CPPTRACE_VERSION_MAJOR ${CMAKE_PROJECT_VERSION_MAJOR})
 set(CPPTRACE_VERSION_MINOR ${CMAKE_PROJECT_VERSION_MINOR})
 set(CPPTRACE_VERSION_PATCH ${CMAKE_PROJECT_VERSION_PATCH})

src/binary/elf.cpp

@@ -424,7 +424,7 @@ namespace detail {
             static std::unordered_map<std::string, Result<elf, internal_error>> cache;
             auto it = cache.find(object_path);
             if(it == cache.end()) {
-                auto res = cache.insert({ object_path, elf::open_elf(object_path) });
+                auto res = cache.emplace(object_path, elf::open_elf(object_path));
                 VERIFY(res.second);
                 it = res.first;
             }

src/formatting.cpp

@@ -208,19 +208,18 @@ namespace cpptrace {
             const auto yellow = color ? YELLOW : "";
             const auto blue   = color ? BLUE : "";
             if(frame.is_inline) {
-                microfmt::print(stream, "{<{}} ", 2 * sizeof(frame_ptr) + 2, "(inlined)");
-            } else if(options.addresses != address_mode::none) {
+                microfmt::print(stream, "{<{}}", 2 * sizeof(frame_ptr) + 2, "(inlined)");
+            } else {
                 auto address = options.addresses == address_mode::raw ? frame.raw_address : frame.object_address;
-                microfmt::print(stream, "{}0x{>{}:0h}{} ", blue, 2 * sizeof(frame_ptr), address, reset);
+                microfmt::print(stream, "{}0x{>{}:0h}{}", blue, 2 * sizeof(frame_ptr), address, reset);
             }
             if(!frame.symbol.empty()) {
-                microfmt::print(stream, "in {}{}{}", yellow, frame.symbol, reset);
+                microfmt::print(stream, " in {}{}{}", yellow, frame.symbol, reset);
             }
             if(!frame.filename.empty()) {
                 microfmt::print(
                     stream,
-                    "{}at {}{}{}",
-                    frame.symbol.empty() ? "" : " ",
+                    " at {}{}{}",
                     green,
                     options.paths == path_mode::full ? frame.filename : detail::basename(frame.filename, true),
                     reset

src/from_current.cpp

@@ -272,7 +272,8 @@ namespace cpptrace {
             memcpy(new_vtable_page, type_info_vtable_pointer, vtable_size * sizeof(void*));
             // ninja in the custom __do_catch interceptor
             auto new_vtable = static_cast<void**>(new_vtable_page);
-            new_vtable[6] = reinterpret_cast<void*>(do_catch_function);
+            // double cast is done here because older (and some newer gcc versions) warned about it under -Wpedantic
+            new_vtable[6] = reinterpret_cast<void*>(reinterpret_cast<std::uintptr_t>(do_catch_function));
             // make the page read-only
             mprotect_page(new_vtable_page, page_size, memory_readonly);
 

src/symbols/dwarf/dwarf_resolver.cpp

@@ -324,7 +324,7 @@ namespace libdwarf {
                     char** dw_srcfiles;
                     Dwarf_Signed dw_filecount;
                     VERIFY(wrap(dwarf_srcfiles, cu_die.get(), &dw_srcfiles, &dw_filecount) == DW_DLV_OK);
-                    it = srcfiles_cache.insert(it, {off, srcfiles{cu_die.dbg, dw_srcfiles, dw_filecount}});
+                    it = srcfiles_cache.emplace_hint(it, off, srcfiles{cu_die.dbg, dw_srcfiles, dw_filecount});
                 }
                 if(file_i < it->second.count()) {
                     // dwarf is using 1-indexing

src/symbols/dwarf/dwarf_utils.hpp

@@ -67,7 +67,14 @@ namespace libdwarf {
     // sorted range entries for dies
     template<
         typename T,
-        typename std::enable_if<std::is_trivially_copyable<T>::value && sizeof(T) <= 16, int>::type = 0
+        typename std::enable_if<
+            // old gcc doesn't support this trait https://godbolt.org/z/fKWT9jTK7
+            #if !(defined(__GNUC__) && (__GNUC__ < 5))
+             std::is_trivially_copyable<T>::value &&
+            #endif
+            sizeof(T) <= 16,
+            int
+        >::type = 0
     >
     class die_cache {
     public:

src/utils/common.hpp

@@ -24,6 +24,13 @@
  #define NODISCARD
 #endif
 
+// workaround a bizarre gcc bug https://godbolt.org/z/s78vnf7jv
+// https://github.com/jeremy-rifkin/cpptrace/issues/220
+#if defined(__GNUC__) && (__GNUC__ < 7)
+ #undef NODISCARD
+ #define NODISCARD
+#endif
+
 #if IS_MSVC
  #define MSVC_CDECL __cdecl
 #else

test/unit/lib/formatting.cpp

@@ -96,21 +96,6 @@ TEST(FormatterTest, ObjectAddresses) {
     );
 }
 
-TEST(FormatterTest, NoAddresses) {
-    auto formatter = cpptrace::formatter{}
-        .addresses(cpptrace::formatter::address_mode::none);
-    auto res = split(formatter.format(make_test_stacktrace()), "\n");
-    EXPECT_THAT(
-        res,
-        ElementsAre(
-            "Stack trace (most recent call first):",
-            "#0 in foo() at foo.cpp:20:30",
-            "#1 in bar() at bar.cpp:30:40",
-            "#2 in main at foo.cpp:40:25"
-        )
-    );
-}
-
 TEST(FormatterTest, PathShortening) {
     cpptrace::stacktrace trace;
     trace.frames.push_back({0x1, 0x1001, {20}, {30}, "/home/foo/foo.cpp", "foo()", false});