c++20 by default

.bazelrc

@@ -64,7 +64,7 @@ common --experimental_allow_tags_propagation
 build:linux --copt=-fdebug-types-section
 build:linux --copt=-fPIC
 build:linux --copt=-Wno-deprecated-declarations
-build:linux --cxxopt=-std=c++17 --host_cxxopt=-std=c++17
+build:linux --cxxopt=-std=c++20 --host_cxxopt=-std=c++20
 build:linux --cxxopt=-fsized-deallocation --host_cxxopt=-fsized-deallocation
 build:linux --conlyopt=-fexceptions
 build:linux --fission=dbg,opt
@@ -133,7 +133,7 @@ build:clang-asan --linkopt --rtlib=compiler-rt
 build:clang-asan --linkopt --unwindlib=libgcc
 
 # macOS
-build:macos --cxxopt=-std=c++17 --host_cxxopt=-std=c++17
+build:macos --cxxopt=-std=c++20 --host_cxxopt=-std=c++20
 build:macos --action_env=PATH=/opt/homebrew/bin:/opt/local/bin:/usr/local/bin:/usr/bin:/bin
 build:macos --host_action_env=PATH=/opt/homebrew/bin:/opt/local/bin:/usr/local/bin:/usr/bin:/bin
 build:macos --define tcmalloc=disabled

contrib/language/filters/http/test/language_integration_test.cc

@@ -21,7 +21,8 @@ name: envoy.filters.http.language
   default_language: {}
   supported_languages: {}
 )EOF";
-    config_helper_.prependFilter(fmt::format(yaml, default_language, supported_languages));
+    config_helper_.prependFilter(
+        fmt::format(fmt::runtime(yaml), default_language, supported_languages));
   }
 };
 

contrib/mysql_proxy/filters/network/test/mysql_integration_test.cc

@@ -24,12 +24,12 @@ class MySQLIntegrationTest : public testing::TestWithParam<Network::Address::IpV
                              public MySQLTestUtils,
                              public BaseIntegrationTest {
   std::string mysqlConfig() {
-    return fmt::format(TestEnvironment::readFileToStringForTest(TestEnvironment::runfilesPath(
-                           "contrib/mysql_proxy/filters/network/test/mysql_test_config.yaml")),
-                       Platform::null_device_path,
-                       Network::Test::getLoopbackAddressString(GetParam()),
-                       Network::Test::getLoopbackAddressString(GetParam()),
-                       Network::Test::getAnyAddressString(GetParam()));
+    return fmt::format(
+        fmt::runtime(TestEnvironment::readFileToStringForTest(TestEnvironment::runfilesPath(
+            "contrib/mysql_proxy/filters/network/test/mysql_test_config.yaml"))),
+        Platform::null_device_path, Network::Test::getLoopbackAddressString(GetParam()),
+        Network::Test::getLoopbackAddressString(GetParam()),
+        Network::Test::getAnyAddressString(GetParam()));
   }
 
 public:

contrib/postgres_proxy/filters/network/test/postgres_integration_test.cc

@@ -34,8 +34,8 @@ class PostgresBaseIntegrationTest : public testing::TestWithParam<Network::Addre
   std::string postgresConfig(SSLConfig downstream_ssl_config, SSLConfig upstream_ssl_config,
                              std::string additional_filters) {
     std::string main_config = fmt::format(
-        TestEnvironment::readFileToStringForTest(TestEnvironment::runfilesPath(
-            "contrib/postgres_proxy/filters/network/test/postgres_test_config.yaml-template")),
+        fmt::runtime(TestEnvironment::readFileToStringForTest(TestEnvironment::runfilesPath(
+            "contrib/postgres_proxy/filters/network/test/postgres_test_config.yaml-template"))),
         Platform::null_device_path, Network::Test::getLoopbackAddressString(GetParam()),
         Network::Test::getLoopbackAddressString(GetParam()),
         std::get<1>(upstream_ssl_config), // upstream SSL transport socket

tools/gen_compilation_database.py

@@ -100,8 +100,8 @@ def modify_compile_command(target, args):
         # depend on Envoy targets.
         if not target["file"].startswith("external/") or target["file"].startswith(
                 "external/envoy"):
-            # *.h file is treated as C header by default while our headers files are all C++17.
-            options = "-x c++ -std=c++17 -fexceptions " + options
+            # *.h file is treated as C header by default while our headers files are all C++20.
+            options = "-x c++ -std=c++20 -fexceptions " + options
 
     target["command"] = " ".join([cc, options])
     return target