fixing definition of CXX11_ABI for gcc-like (#10165)

* fixing definition of CXX11_ABI for gcc-like

* fix test

* added conf and tests

conan/tools/cmake/toolchain.py

@@ -187,12 +187,12 @@ def context(self):
                    }.get(libcxx)
             if lib:
                 lib = "-library={}".format(lib)
-        elif compiler == "gcc":
-            # we might want to remove this "1", it is the default in most distros
-            if libcxx == "libstdc++11":
-                glib = "1"
-            elif libcxx == "libstdc++":
+
+        if compiler in ['clang', 'apple-clang', 'gcc']:
+            if libcxx == "libstdc++":
                 glib = "0"
+            elif libcxx == "libstdc++11" and self._conanfile.conf["tools.gnu:define_libcxx11_abi"]:
+                glib = "1"
         return {"set_libcxx": lib, "glibcxx": glib}
 
 

conan/tools/gnu/autotoolstoolchain.py

@@ -72,9 +72,11 @@ def _cxx11_abi_define(self):
             return
 
         compiler = settings.get_safe("compiler.base") or settings.get_safe("compiler")
-        if compiler == "gcc":
+        if compiler in ['clang', 'apple-clang', 'gcc']:
             if libcxx == 'libstdc++':
                 return '_GLIBCXX_USE_CXX11_ABI=0'
+            elif libcxx == "libstdc++11" and self._conanfile.conf["tools.gnu:define_libcxx11_abi"]:
+                return '_GLIBCXX_USE_CXX11_ABI=1'
 
     def _libcxx(self):
         settings = self._conanfile.settings

conans/model/conf.py

@@ -22,6 +22,7 @@
     "tools.files.download:retry": "Number of retries in case of failure when downloading",
     "tools.files.download:retry_wait": "Seconds to wait between download attempts",
     "tools.gnu:make_program": "Indicate path to make program",
+    "tools.gnu:define_libcxx11_abi": "Force definition of GLIBCXX_USE_CXX11_ABI=1 for libstdc++11",
     "tools.google.bazel:config": "Define Bazel config file",
     "tools.google.bazel:bazelrc_path": "Defines Bazel rc-path",
     "tools.microsoft.msbuild:verbosity": "Verbosity level for MSBuild: "

conans/test/functional/toolchains/cmake/test_cmake.py

@@ -352,8 +352,8 @@ def test_toolchain_linux(self, build_type, cppstd, arch, libcxx, shared):
 
         extensions_str = "ON" if "gnu" in cppstd else "OFF"
         arch_str = "-m32" if arch == "x86" else "-m64"
-        cxx11_abi_str = "1" if libcxx == "libstdc++11" else "0"
-        defines = '_GLIBCXX_USE_CXX11_ABI=%s;MYDEFINE="MYDEF_VALUE";MYDEFINEINT=42;'\
+        cxx11_abi_str = "_GLIBCXX_USE_CXX11_ABI=0;" if libcxx == "libstdc++" else ""
+        defines = '%sMYDEFINE="MYDEF_VALUE";MYDEFINEINT=42;'\
                   'MYDEFINE_CONFIG=$<IF:$<CONFIG:debug>,"MYDEF_DEBUG",$<IF:$<CONFIG:release>,'\
                   '"MYDEF_RELEASE","">>;MYDEFINEINT_CONFIG=$<IF:$<CONFIG:debug>,421,'\
                   '$<IF:$<CONFIG:release>,422,"">>' % cxx11_abi_str

conans/test/unittests/client/toolchain/autotools/autotools_toolchain_test.py

@@ -203,12 +203,23 @@ def test_cxx11_abi_define():
     be = AutotoolsToolchain(conanfile)
     env = be.vars()
     assert be.gcc_cxx11_abi is None
-    assert "-D_GLIBCXX_USE_CXX11_ABI=0" not in env["CPPFLAGS"]
+    assert "GLIBCXX_USE_CXX11_ABI" not in env["CPPFLAGS"]
+
+    # Force the GLIBCXX_USE_CXX11_ABI=1 for old distros is direct def f ``gcc_cxx11_abi``
+    be.gcc_cxx11_abi = "_GLIBCXX_USE_CXX11_ABI=1"
+    env = be.vars()
+    assert "-D_GLIBCXX_USE_CXX11_ABI=1" in env["CPPFLAGS"]
+
+    # Also conf is possible
+    conanfile.conf["tools.gnu:define_libcxx11_abi"] = True
+    be = AutotoolsToolchain(conanfile)
+    env = be.vars()
+    assert "-D_GLIBCXX_USE_CXX11_ABI=1" in env["CPPFLAGS"]
 
 
 @pytest.mark.parametrize("config", [
     ('x86_64', "-m64"),
-    ('x86', "-m32"),])
+    ('x86', "-m32")])
 def test_architecture_flag(config):
     """Architecture flag is set in CXXFLAGS, CFLAGS and LDFLAGS"""
     arch, expected = config

conans/test/unittests/tools/cmake/test_cmaketoolchain.py

@@ -6,6 +6,7 @@
 from conan.tools.cmake import CMakeToolchain
 from conan.tools.cmake.toolchain import Block, GenericSystemBlock
 from conans import ConanFile, Settings
+from conans.client.conf import get_default_settings_yml
 from conans.model.conf import Conf
 from conans.model.env_info import EnvValues
 
@@ -331,3 +332,39 @@ def test_fpic_enabled(conanfile_linux_fpic):
     toolchain = CMakeToolchain(conanfile_linux_fpic)
     content = toolchain.content
     assert 'set(CMAKE_POSITION_INDEPENDENT_CODE ON' in content
+
+
+def test_libcxx_abi_flag():
+    c = ConanFile(Mock(), None)
+    c.settings = "os", "compiler", "build_type", "arch"
+    c.initialize(Settings.loads(get_default_settings_yml()), EnvValues())
+    c.settings.build_type = "Release"
+    c.settings.arch = "x86_64"
+    c.settings.compiler = "gcc"
+    c.settings.compiler.version = "11"
+    c.settings.compiler.cppstd = "20"
+    c.settings.compiler.libcxx = "libstdc++"
+    c.settings.os = "Linux"
+    c.conf = Conf()
+    c.folders.set_base_generators(".")
+    c._conan_node = Mock()
+    c._conan_node.dependencies = []
+
+    toolchain = CMakeToolchain(c)
+    content = toolchain.content
+    assert '-D_GLIBCXX_USE_CXX11_ABI=0' in content
+    c.settings.compiler.libcxx = "libstdc++11"
+    toolchain = CMakeToolchain(c)
+    content = toolchain.content
+    # by default, no flag is output anymore, it is assumed the compiler default
+    assert 'GLIBCXX_USE_CXX11_ABI' not in content
+    # recipe workaround for older distros
+    toolchain.blocks["libcxx"].values["glibcxx"] = "1"
+    content = toolchain.content
+    assert '-D_GLIBCXX_USE_CXX11_ABI=1' in content
+
+    # but maybe the conf is better
+    c.conf["tools.gnu:define_libcxx11_abi"] = True
+    toolchain = CMakeToolchain(c)
+    content = toolchain.content
+    assert '-D_GLIBCXX_USE_CXX11_ABI=1' in content