tvl-depot/absl/copts/copts.py
Loo Rong Jie 253eb74164 [CMake] Set correct flags for clang-cl (#278)
clang-cl produce binaries with MSVC ABI and wants to be as flag-compatible with pure MSVC as possible, so this leads to all sorts of weird cases.

clang-cl alias /Wall as clang's -Weverything which is way too verbose, so it needs /W3 like pure MSVC.
clang-cl only understand GCC style warning flags (-W[no]blah) and just silent drop MSVC style warning flags (/wd[num]).
clang-cl needs MSVC define flags since it is consuming the same header files as pure MSVC.
CMake set CMAKE_CXX_COMPILER_ID as Clang when clang-cl is detected, so need extra if (MSVC) to differentiate it.

We are not doing clang-cl specialization in Bazel as currently there is no reliable way to detect clang-cl in Bazel..

This PR should be NFC for LLVM/GCC users on Unix platforms.

Other changes:

Add ABSL_ prefix to variable names to avoid name collision in CMake.
2019-03-22 15:23:01 -04:00

178 lines
5.8 KiB
Python

"""Abseil compiler options.
This is the source of truth for Abseil compiler options. To modify Abseil
compilation options:
(1) Edit the appropriate list in this file based on the platform the flag is
needed on.
(2) Run `<path_to_absl>/copts/generate_copts.py`.
The generated copts are consumed by configure_copts.bzl and
AbseilConfigureCopts.cmake.
"""
# /Wall with msvc includes unhelpful warnings such as C4711, C4710, ...
MSVC_BIG_WARNING_FLAGS = [
"/W3",
]
LLVM_BIG_WARNING_FLAGS = [
"-Wall",
"-Wextra",
"-Weverything",
]
# Docs on single flags is preceded by a comment.
# Docs on groups of flags is preceded by ###.
LLVM_DISABLE_WARNINGS_FLAGS = [
# Abseil does not support C++98
"-Wno-c++98-compat-pedantic",
# Turns off all implicit conversion warnings. Most are re-enabled below.
"-Wno-conversion",
"-Wno-covered-switch-default",
"-Wno-deprecated",
"-Wno-disabled-macro-expansion",
"-Wno-double-promotion",
###
# Turned off as they include valid C++ code.
"-Wno-comma",
"-Wno-extra-semi",
"-Wno-extra-semi-stmt",
"-Wno-packed",
"-Wno-padded",
###
# Google style does not use unsigned integers, though STL containers
# have unsigned types.
"-Wno-sign-compare",
###
"-Wno-float-conversion",
"-Wno-float-equal",
"-Wno-format-nonliteral",
# Too aggressive: warns on Clang extensions enclosed in Clang-only
# compilation paths.
"-Wno-gcc-compat",
###
# Some internal globals are necessary. Don't do this at home.
"-Wno-global-constructors",
"-Wno-exit-time-destructors",
###
"-Wno-nested-anon-types",
"-Wno-non-modular-include-in-module",
"-Wno-old-style-cast",
# Warns on preferred usage of non-POD types such as string_view
"-Wno-range-loop-analysis",
"-Wno-reserved-id-macro",
"-Wno-shorten-64-to-32",
"-Wno-switch-enum",
"-Wno-thread-safety-negative",
"-Wno-undef",
"-Wno-unknown-warning-option",
"-Wno-unreachable-code",
# Causes warnings on include guards
"-Wno-unused-macros",
"-Wno-weak-vtables",
###
# Implicit conversion warnings turned off by -Wno-conversion
# which are re-enabled below.
"-Wbitfield-enum-conversion",
"-Wbool-conversion",
"-Wconstant-conversion",
"-Wenum-conversion",
"-Wint-conversion",
"-Wliteral-conversion",
"-Wnon-literal-null-conversion",
"-Wnull-conversion",
"-Wobjc-literal-conversion",
"-Wno-sign-conversion",
"-Wstring-conversion",
]
LLVM_TEST_DISABLE_WARNINGS_FLAGS = [
"-Wno-c99-extensions",
"-Wno-missing-noreturn",
"-Wno-missing-prototypes",
"-Wno-missing-variable-declarations",
"-Wno-null-conversion",
"-Wno-shadow",
"-Wno-shift-sign-overflow",
"-Wno-sign-compare",
"-Wno-unused-function",
"-Wno-unused-member-function",
"-Wno-unused-parameter",
"-Wno-unused-private-field",
"-Wno-unused-template",
"-Wno-used-but-marked-unused",
"-Wno-zero-as-null-pointer-constant",
# gtest depends on this GNU extension being offered.
"-Wno-gnu-zero-variadic-macro-arguments",
]
MSVC_STYLE_EXCEPTIONS_FLAGS = [
"/U_HAS_EXCEPTIONS", "/D_HAS_EXCEPTIONS=1", "/EHsc"
]
MSVC_DEFINES = [
"/DNOMINMAX", # Don't define min and max macros (windows.h)
# Don't bloat namespace with incompatible winsock versions.
"/DWIN32_LEAN_AND_MEAN",
# Don't warn about usage of insecure C functions.
"/D_CRT_SECURE_NO_WARNINGS",
"/D_SCL_SECURE_NO_WARNINGS",
# Introduced in VS 2017 15.8, allow overaligned types in aligned_storage
"/D_ENABLE_EXTENDED_ALIGNED_STORAGE",
]
COPT_VARS = {
"ABSL_GCC_FLAGS": [
"-Wall",
"-Wextra",
"-Wcast-qual",
"-Wconversion-null",
"-Wmissing-declarations",
"-Woverlength-strings",
"-Wpointer-arith",
"-Wunused-local-typedefs",
"-Wunused-result",
"-Wvarargs",
"-Wvla", # variable-length array
"-Wwrite-strings",
# gcc-4.x has spurious missing field initializer warnings.
# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=36750
# Remove when gcc-4.x is no longer supported.
"-Wno-missing-field-initializers",
# Google style does not use unsigned integers, though STL containers
# have unsigned types.
"-Wno-sign-compare",
],
"ABSL_GCC_TEST_FLAGS": [
"-Wno-conversion-null",
"-Wno-missing-declarations",
"-Wno-sign-compare",
"-Wno-unused-function",
"-Wno-unused-parameter",
"-Wno-unused-private-field",
],
"ABSL_GCC_EXCEPTIONS_FLAGS": ["-fexceptions"],
"ABSL_LLVM_FLAGS": LLVM_BIG_WARNING_FLAGS + LLVM_DISABLE_WARNINGS_FLAGS,
"ABSL_LLVM_TEST_FLAGS": LLVM_TEST_DISABLE_WARNINGS_FLAGS,
"ABSL_LLVM_EXCEPTIONS_FLAGS": ["-fexceptions"],
"ABSL_CLANG_CL_FLAGS": (MSVC_BIG_WARNING_FLAGS +
LLVM_DISABLE_WARNINGS_FLAGS + MSVC_DEFINES),
"ABSL_CLANG_CL_TEST_FLAGS": LLVM_TEST_DISABLE_WARNINGS_FLAGS,
"ABSL_CLANG_CL_EXCEPTIONS_FLAGS": MSVC_STYLE_EXCEPTIONS_FLAGS,
"ABSL_MSVC_FLAGS": MSVC_BIG_WARNING_FLAGS + MSVC_DEFINES + [
"/wd4005", # macro-redefinition
"/wd4068", # unknown pragma
"/wd4180", # qualifier applied to function type has no meaning; ignored
"/wd4244", # conversion from 'type1' to 'type2', possible loss of data
"/wd4267", # conversion from 'size_t' to 'type', possible loss of data
# forcing value to bool 'true' or 'false' (performance warning)
"/wd4800",
],
"ABSL_MSVC_TEST_FLAGS": [
"/wd4018", # signed/unsigned mismatch
"/wd4101", # unreferenced local variable
"/wd4503", # decorated name length exceeded, name was truncated
],
"ABSL_MSVC_EXCEPTIONS_FLAGS": MSVC_STYLE_EXCEPTIONS_FLAGS,
}