Add more compilers to CI and increase FMT_PEDANTIC warning levels

.travis.yml

@@ -1,29 +1,94 @@
 language: cpp
 dist: trusty
-sudo: required # the doc target uses sudo to install dependencies
+sudo: false
+
+os: linux
+
+git:
+  depth: 1
 
-os:
-  - linux
-  - osx
 
 env:
   global:
     - secure: |-
         a1eovNn4uol9won7ghr67eD3/59oeESN+G9bWE+ecI1V6yRseG9whniGhIpC/YfMW/Qz5I
         5sxSmFjaw9bxCISNwUIrL1O5x2AmRYTnFcXk4dFsUvlZg+WeF/aKyBYCNRM8C2ndbBmtAO
         o1F2EwFbiso0EmtzhAPs19ujiVxkLn4=
-  matrix:
-    - BUILD=Doc
-    - BUILD=Debug STANDARD=14
-    - BUILD=Release STANDARD=14
 
 matrix:
-  exclude:
-    - os: osx
-      env: BUILD=Doc
   include:
+      # Documentation
+    - env: BUILD=Doc
+      sudo: required
+      # g++ 6 on Linux with C++14
+    - env: COMPILER=g++-6 BUILD=Debug STANDARD=14
+      compiler: gcc
+      addons:
+        apt:
+          update: true
+          sources:
+            - ubuntu-toolchain-r-test
+          packages:
+            - g++-6
+    - env: COMPILER=g++-6 BUILD=Release STANDARD=14
+      compiler: gcc
+      addons:
+        apt:
+          update: true
+          sources:
+            - ubuntu-toolchain-r-test
+          packages:
+            - g++-6
+      # Apple clang on OS X with C++14
+    - env: BUILD=Debug STANDARD=14
+      compiler: clang
+      os: osx
+    - env: BUILD=Release STANDARD=14
+      compiler: clang
+      os: osx
+      # clang 6.0 on Linux with C++14
+    - env: COMPILER=clang++-6.0 BUILD=Debug STANDARD=14
+      compiler: clang
+      addons:
+        apt:
+          update: true
+          packages:
+            - clang-6.0
+          sources:
+            - ubuntu-toolchain-r-test
+            - llvm-toolchain-trusty
+            - llvm-toolchain-trusty-6.0
+      # clang 4.0 on Linux with C++14
+    - env: COMPILER=clang++-4.0 BUILD=Debug STANDARD=11
+      compiler: clang
+      addons:
+        apt:
+          update: true
+          packages:
+            - clang-4.0
+          sources:
+            - ubuntu-toolchain-r-test
+            - llvm-toolchain-trusty
+            - llvm-toolchain-trusty-4.0
+      # g++ 4.8 on Linux with C++11
+    - env: COMPILER=g++-4.8 BUILD=Debug STANDARD=11
+      compiler: gcc
+      # g++ 4.4 on Linux with C++11
+    - env: COMPILER=g++-4.4 BUILD=Debug STANDARD=11
+      compiler: gcc
+      addons:
+        apt:
+          update: true
+          packages:
+            - g++-4.4
+          sources:
+            - ubuntu-toolchain-r-test
+      # Android
     - language: android
       android:
+      addons:
+        apt:
+          update: true
       components:
         - tools
         - platform-tools
@@ -51,17 +116,14 @@ matrix:
       after_success:
         - cd ${TRAVIS_BUILD_DIR}
         - tree ./libs
+  allow_failures:
+      # Errors
+    - env: COMPILER=g++-4.4 BUILD=Debug STANDARD=11
+      compiler: gcc
 
-# Install gcc-6 for extended constexpr support.
-addons:
-  apt:
-    sources:
-    - ubuntu-toolchain-r-test
-    packages:
-    - g++-6
-
-before_install:
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then export CXX=g++-6; fi
+before_script:
+  - if [[ "${TRAVIS_OS_NAME}" == "linux" ]]; then export CXX=${COMPILER}; fi
+  - if [[ "${BUILD}" != "Doc" ]]; then ${CXX} --version; fi
 
 script:
   - support/travis-build.py

CMakeLists.txt

@@ -1,6 +1,6 @@
 message(STATUS "CMake version: ${CMAKE_VERSION}")
 
-cmake_minimum_required(VERSION 2.8.12)
+cmake_minimum_required(VERSION 3.1.0)
 
 # Determine if fmt is built as a subproject (using add_subdirectory)
 # or if it is the master project.
@@ -28,12 +28,12 @@ if (NOT CMAKE_BUILD_TYPE)
 endif ()
 
 option(FMT_PEDANTIC "Enable extra warnings and expensive tests." OFF)
+option(FMT_WERROR "Halt the compilation with an error on compiler warnings." OFF)
 
 # Options that control generation of various targets.
 option(FMT_DOC "Generate the doc target." ${MASTER_PROJECT})
 option(FMT_INSTALL "Generate the install target." ${MASTER_PROJECT})
 option(FMT_TEST "Generate the test target." ${MASTER_PROJECT})
-option(FMT_USE_CPP14 "Enable the addition of C++14 compiler flags." ON)
 
 project(FMT)
 
@@ -58,9 +58,62 @@ set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH}
   "${CMAKE_CURRENT_SOURCE_DIR}/support/cmake")
 
 include(cxx14)
+include(CheckCXXCompilerFlag)
+
+if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
+  set(PEDANTIC_COMPILE_FLAGS -pedantic-errors -Wall -Wextra -pedantic
+      -Wold-style-cast -Wfloat-equal -Wlogical-op -Wundef
+      -Wredundant-decls -Wshadow -Wwrite-strings -Wpointer-arith
+      -Wcast-qual -Wformat=2 -Wmissing-include-dirs
+      -Wcast-align -Wnon-virtual-dtor
+      -Wctor-dtor-privacy -Wdisabled-optimization
+      -Winvalid-pch -Wmissing-declarations -Woverloaded-virtual
+      -Wno-sign-conversion -Wno-shadow -Wno-format-nonliteral
+      -Wno-dangling-else -Wno-ctor-dtor-privacy)
+  if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.6)
+      set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wnoexcept)
+  endif ()
+  if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5.0)
+      set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wdouble-promotion
+          -Wtrampolines -Wzero-as-null-pointer-constant -Wuseless-cast
+          -Wvector-operation-performance -Wsized-deallocation)
+  endif ()
+  if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 6.0)
+      set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wshift-overflow=2
+          -Wnull-dereference -Wduplicated-cond)
+  endif ()
+
+  set(WERROR_FLAG -Werror)
+endif ()
+
+if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+  set(PEDANTIC_COMPILE_FLAGS -Weverything -Wpedantic
+      -Wno-weak-vtables -Wno-padded -Wno-gnu-statement-expression
+      -Wno-c++98-compat -Wno-c++98-compat-pedantic -Wno-reserved-id-macro
+      -Wno-global-constructors -Wno-disabled-macro-expansion
+      -Wno-switch-enum -Wno-documentation-unknown-command
+      -Wno-gnu-string-literal-operator-template -Wno-unused-member-function
+      -Wno-format-nonliteral -Wno-missing-noreturn -Wno-undefined-func-template
+      -Wno-shadow -Wno-sign-conversion -Wno-used-but-marked-unused
+      -Wno-covered-switch-default -Wno-missing-variable-declarations
+      -Wno-double-promotion)
+
+  set(WERROR_FLAG -Werror)
+
+  check_cxx_compiler_flag(-Wno-zero-as-null-pointer-constant HAS_NULLPTR_WARNING)
+  if (HAS_NULLPTR_WARNING)
+    set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wno-zero-as-null-pointer-constant)
+  endif ()
 
-if (CMAKE_COMPILER_IS_GNUCXX OR (CMAKE_CXX_COMPILER_ID MATCHES "Clang"))
-  set(PEDANTIC_COMPILE_FLAGS -Wall -Wextra -Wshadow -pedantic)
+  check_cxx_compiler_flag(-Wno-gnu-string-literal-operator-template HAS_GNU_UDL_WARNING)
+  if (HAS_GNU_UDL_WARNING)
+    set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS} -Wno-gnu-string-literal-operator-template)
+  endif ()
+endif ()
+
+if (MSVC)
+  set(PEDANTIC_COMPILE_FLAGS /W4)
+  set(WERROR_FLAG /WX)
 endif ()
 
 if (MASTER_PROJECT AND CMAKE_GENERATOR MATCHES "Visual Studio")
@@ -106,9 +159,9 @@ endif ()
 add_library(fmt ${FMT_SOURCES} ${FMT_HEADERS} README.rst ChangeLog.rst)
 add_library(fmt::fmt ALIAS fmt)
 
-# Starting with CMake 3.1 the CXX_STANDARD property can be used instead.
-# Don't export -std since it may break projects that use other standards.
-target_compile_options(fmt PRIVATE ${CPP14_FLAG})
+if (FMT_WERROR)
+  target_compile_options(fmt PRIVATE ${WERROR_FLAG})
+endif ()
 if (FMT_PEDANTIC)
   target_compile_options(fmt PRIVATE ${PEDANTIC_COMPILE_FLAGS})
 endif ()
@@ -130,17 +183,14 @@ if (BUILD_SHARED_LIBS)
   target_compile_definitions(fmt PRIVATE FMT_EXPORT INTERFACE FMT_SHARED)
 endif ()
 
-# Additionally define a header-only library when CMake is new enough.
-if (CMAKE_VERSION VERSION_GREATER 3.1.0 OR CMAKE_VERSION VERSION_EQUAL 3.1.0)
-  add_library(fmt-header-only INTERFACE)
-  add_library(fmt::fmt-header-only ALIAS fmt-header-only)
+add_library(fmt-header-only INTERFACE)
+add_library(fmt::fmt-header-only ALIAS fmt-header-only)
 
-  target_compile_definitions(fmt-header-only INTERFACE FMT_HEADER_ONLY=1)
+target_compile_definitions(fmt-header-only INTERFACE FMT_HEADER_ONLY=1)
 
-  target_include_directories(fmt-header-only INTERFACE
-    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
-    $<INSTALL_INTERFACE:include>)
-endif ()
+target_include_directories(fmt-header-only INTERFACE
+  $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
+  $<INSTALL_INTERFACE:include>)
 
 # Install targets.
 if (FMT_INSTALL)

include/fmt/core.h

@@ -30,6 +30,12 @@
 # define FMT_HAS_INCLUDE(x) 0
 #endif
 
+#ifdef __has_cpp_attribute
+# define FMT_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
+#else
+# define FMT_HAS_CPP_ATTRIBUTE(x) 0
+#endif
+
 #if defined(__GNUC__) && !defined(__clang__)
 # define FMT_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
 #else
@@ -95,6 +101,12 @@
 # define FMT_USE_NULLPTR 0
 #endif
 
+#if FMT_HAS_CPP_ATTRIBUTE(noreturn)
+# define FMT_NORETURN [[noreturn]]
+#else
+# define FMT_NORETURN /*noreturn*/
+#endif
+
 // Check if exceptions are disabled.
 #if defined(__GNUC__) && !defined(__EXCEPTIONS)
 # define FMT_EXCEPTIONS 0
@@ -218,7 +230,7 @@ class basic_string_view {
 #else
   struct type {
     const char *data() const { return FMT_NULL; }
-    size_t size() const { return 0; };
+    size_t size() const { return 0; }
   };
 #endif
 
@@ -550,11 +562,17 @@ FMT_CONSTEXPR basic_format_arg<Context> make_arg(const T &value);
     return static_cast<ValueType>(val); \
   }
 
+#define FMT_MAKE_VALUE_SAME(TAG, Type) \
+  template <typename C> \
+  FMT_CONSTEXPR typed_value<C, TAG> make_value(Type val) { \
+    return val; \
+  }
+
 FMT_MAKE_VALUE(bool_type, bool, int)
 FMT_MAKE_VALUE(int_type, short, int)
 FMT_MAKE_VALUE(uint_type, unsigned short, unsigned)
-FMT_MAKE_VALUE(int_type, int, int)
-FMT_MAKE_VALUE(uint_type, unsigned, unsigned)
+FMT_MAKE_VALUE_SAME(int_type, int)
+FMT_MAKE_VALUE_SAME(uint_type, unsigned)
 
 // To minimize the number of types we need to deal with, long is translated
 // either to int or to long long depending on its size.
@@ -568,8 +586,8 @@ FMT_MAKE_VALUE(
     (sizeof(unsigned long) == sizeof(unsigned) ? uint_type : ulong_long_type),
     unsigned long, ulong_type)
 
-FMT_MAKE_VALUE(long_long_type, long long, long long)
-FMT_MAKE_VALUE(ulong_long_type, unsigned long long, unsigned long long)
+FMT_MAKE_VALUE_SAME(long_long_type, long long)
+FMT_MAKE_VALUE_SAME(ulong_long_type, unsigned long long)
 FMT_MAKE_VALUE(int_type, signed char, int)
 FMT_MAKE_VALUE(uint_type, unsigned char, unsigned)
 FMT_MAKE_VALUE(char_type, char, int)
@@ -583,8 +601,8 @@ inline typed_value<C, char_type> make_value(wchar_t val) {
 #endif
 
 FMT_MAKE_VALUE(double_type, float, double)
-FMT_MAKE_VALUE(double_type, double, double)
-FMT_MAKE_VALUE(long_double_type, long double, long double)
+FMT_MAKE_VALUE_SAME(double_type, double)
+FMT_MAKE_VALUE_SAME(long_double_type, long double)
 
 // Formatting of wide strings into a narrow buffer and multibyte strings
 // into a wide buffer is disallowed (https://github.com/fmtlib/fmt/pull/606).
@@ -594,18 +612,17 @@ FMT_MAKE_VALUE(cstring_type, const typename C::char_type*,
                const typename C::char_type*)
 
 FMT_MAKE_VALUE(cstring_type, signed char*, const signed char*)
-FMT_MAKE_VALUE(cstring_type, const signed char*, const signed char*)
+FMT_MAKE_VALUE_SAME(cstring_type, const signed char*)
 FMT_MAKE_VALUE(cstring_type, unsigned char*, const unsigned char*)
-FMT_MAKE_VALUE(cstring_type, const unsigned char*, const unsigned char*)
-FMT_MAKE_VALUE(string_type, basic_string_view<typename C::char_type>,
-               basic_string_view<typename C::char_type>)
+FMT_MAKE_VALUE_SAME(cstring_type, const unsigned char*)
+FMT_MAKE_VALUE_SAME(string_type, basic_string_view<typename C::char_type>)
 FMT_MAKE_VALUE(string_type,
                typename basic_string_view<typename C::char_type>::type,
                basic_string_view<typename C::char_type>)
 FMT_MAKE_VALUE(string_type, const std::basic_string<typename C::char_type>&,
                basic_string_view<typename C::char_type>)
 FMT_MAKE_VALUE(pointer_type, void*, const void*)
-FMT_MAKE_VALUE(pointer_type, const void*, const void*)
+FMT_MAKE_VALUE_SAME(pointer_type, const void*)
 
 #if FMT_USE_NULLPTR
 FMT_MAKE_VALUE(pointer_type, std::nullptr_t, const void*)

include/fmt/format-inl.h

@@ -45,12 +45,6 @@
 # define FMT_CATCH(x) if (false)
 #endif
 
-#ifdef __GNUC__
-// Disable the warning about declaration shadowing because it affects too
-// many valid cases.
-# pragma GCC diagnostic ignored "-Wshadow"
-#endif
-
 #ifdef _MSC_VER
 # pragma warning(push)
 # pragma warning(disable: 4127)  // conditional expression is constant
@@ -71,9 +65,6 @@ inline fmt::internal::null<> strerror_s(char *, std::size_t, ...) {
 
 FMT_BEGIN_NAMESPACE
 
-FMT_FUNC format_error::~format_error() throw() {}
-FMT_FUNC system_error::~system_error() FMT_DTOR_NOEXCEPT {}
-
 namespace {
 
 #ifndef _MSC_VER