Visual Studio w/ Clang will not compile

[LukeMauldin]

Multiple compile errors with Visual Studio 2015 Update 2 RC and Clang.

Steps to reproduce:
Create new project: Templates -> Visual C++ -> Cross Platform -> Dynamic Library (windows) for Clang 3.7 with Microsoft Code Generation

Add spdlog files into project and try to compile and include "spdlog.h".
Output of errors

1>------ Build started: Project: Clangspdlog, Configuration: Debug Win32 ------
1>  dllmain.cpp
1>  format.cc
1>  In file included from spdlog\details\format.cc:28:
1>spdlog\details/format.h(93,10): warning : unknown pragma ignored [-Wunknown-pragmas]
1>  # pragma intrinsic(_BitScanReverse)
1>           ^
1>spdlog\details/format.h(938,10): warning : 'FMT_BUILTIN_CLZ' macro redefined [-Wmacro-redefined]
1>  # define FMT_BUILTIN_CLZ(n) __builtin_clz(n)
1>           ^
1>  spdlog\details/format.h(100,10) :  note: previous definition is here
1>  # define FMT_BUILTIN_CLZ(n) fmt::internal::clz(n)
1>           ^
1>spdlog\details/format.h(942,10): warning : 'FMT_BUILTIN_CLZLL' macro redefined [-Wmacro-redefined]
1>  # define FMT_BUILTIN_CLZLL(n) __builtin_clzll(n)
1>           ^
1>  spdlog\details/format.h(121,10) :  note: previous definition is here
1>  # define FMT_BUILTIN_CLZLL(n) fmt::internal::clzll(n)
1>           ^
1>spdlog\details/format.cc(80,37): error : redefinition of 'strerror_r'
1>  static inline fmt::internal::Null<> strerror_r(int, char *, ...) {
1>                                      ^
1>  spdlog\details/format.cc(80,37) :  note: previous definition is here
1>  static inline fmt::internal::Null<> strerror_r(int, char *, ...) {
1>                                      ^
1>spdlog\details/format.cc(83,37): error : redefinition of 'strerror_s'
1>  static inline fmt::internal::Null<> strerror_s(char *, std::size_t, ...) {
1>                                      ^
1>  spdlog\details/format.cc(83,37) :  note: previous definition is here
1>  static inline fmt::internal::Null<> strerror_s(char *, std::size_t, ...) {
1>                                      ^
1>spdlog\details/format.cc(93,12): error : redefinition of 'fmt_snprintf'
1>  inline int fmt_snprintf(char *buffer, size_t size, const char *format, ...) {
1>             ^
1>  spdlog\details/format.cc(93,12) :  note: previous definition is here
1>  inline int fmt_snprintf(char *buffer, size_t size, const char *format, ...) {
1>             ^
1>spdlog\details/format.cc(112,8): error : redefinition of 'IntChecker'
1>  struct IntChecker {
1>         ^
1>  spdlog\details/format.cc(112,8) :  note: previous definition is here
1>  struct IntChecker {
1>         ^
1>spdlog\details/format.cc(124,8): error : redefinition of 'fmt::(anonymous namespace)::IntChecker<true>'
1>  struct IntChecker<true> {
1>         ^~~~~~~~~~~~~~~~
1>  spdlog\details/format.cc(124,8) :  note: previous definition is here
1>  struct IntChecker<true> {
1>         ^
1>spdlog\details/format.cc(134,12): error : redefinition of 'RESET_COLOR'
1>  const char RESET_COLOR[] = "\x1b[0m";
1>             ^
1>  spdlog\details/format.cc(134,12) :  note: previous definition is here
1>  const char RESET_COLOR[] = "\x1b[0m";
1>             ^
1>spdlog\details/format.cc(147,5): error : redefinition of 'safe_strerror'
1>  int safe_strerror(
1>      ^
1>  spdlog\details/format.cc(147,5) :  note: previous definition is here
1>  int safe_strerror(
1>      ^
1>spdlog\details/format.cc(190,23): warning : 'strerror' is deprecated: This function or variable may be unsafe. Consider using strerror_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details. [-Wdeprecated-declarations]
1>              buffer_ = strerror(error_code_);
1>                        ^
1>  C:\Program Files (x86)\Windows Kits\10\Include\10.0.10240.0\ucrt\string.h(178,24) :  note: 'strerror' has been explicitly marked deprecated here
1>  _ACRTIMP char* __cdecl strerror(
1>                         ^
1>spdlog\details/format.cc(206,6): error : redefinition of 'format_error_code'
1>  void format_error_code(fmt::Writer &out, int error_code,
1>       ^
1>  spdlog\details/format.cc(206,6) :  note: previous definition is here
1>  void format_error_code(fmt::Writer &out, int error_code,
1>       ^
1>spdlog\details/format.cc(224,6): error : redefinition of 'report_error'
1>  void report_error(FormatFunc func,
1>       ^
1>  spdlog\details/format.cc(224,6) :  note: previous definition is here
1>  void report_error(FormatFunc func,
1>       ^
1>spdlog\details/format.cc(235,7): error : redefinition of 'IsZeroInt'
1>  class IsZeroInt : public fmt::internal::ArgVisitor<IsZeroInt, bool> {
1>        ^
1>  spdlog\details/format.cc(235,7) :  note: previous definition is here
1>  class IsZeroInt : public fmt::internal::ArgVisitor<IsZeroInt, bool> {
1>        ^
1>spdlog\details/format.cc(245,7): error : redefinition of 'WidthHandler'
1>  class WidthHandler : public fmt::internal::ArgVisitor<WidthHandler, unsigned> {
1>        ^
1>  spdlog\details/format.cc(245,7) :  note: previous definition is here
1>  class WidthHandler : public fmt::internal::ArgVisitor<WidthHandler, unsigned> {
1>        ^
1>spdlog\details/format.cc(272,7): error : redefinition of 'PrecisionHandler'
1>  class PrecisionHandler :
1>        ^
1>  spdlog\details/format.cc(272,7) :  note: previous definition is here
1>  class PrecisionHandler :
1>        ^
1>spdlog\details/format.cc(289,7): error : redefinition of 'ArgConverter'
1>  class ArgConverter : public fmt::internal::ArgVisitor<ArgConverter<T>, void> {
1>        ^
1>  spdlog\details/format.cc(289,7) :  note: previous definition is here
1>  class ArgConverter : public fmt::internal::ArgVisitor<ArgConverter<T>, void> {
1>        ^
1>spdlog\details/format.cc(337,7): error : redefinition of 'CharConverter'
1>  class CharConverter : public fmt::internal::ArgVisitor<CharConverter, void> {
1>        ^
1>  spdlog\details/format.cc(337,7) :  note: previous definition is here
1>  class CharConverter : public fmt::internal::ArgVisitor<CharConverter, void> {
1>        ^
1>spdlog\details/format.cc(357,7): error : redefinition of 'PrintfArgFormatter'
1>  class PrintfArgFormatter :
1>        ^
1>  spdlog\details/format.cc(357,7) :  note: previous definition is here
1>  class PrintfArgFormatter :
1>        ^
1>spdlog\details/format.cc(429,33): error : redefinition of 'init'
1>  FMT_FUNC void fmt::SystemError::init(
1>                                  ^
1>  spdlog\details/format.cc(429,33) :  note: previous definition is here
1>  FMT_FUNC void fmt::SystemError::init(
1>                                  ^
1>spdlog\details/format.cc(439,38): error : redefinition of 'format_float'
1>  int fmt::internal::CharTraits<char>::format_float(
1>                                       ^
1>  spdlog\details/format.cc(439,38) :  note: previous definition is here
1>  int fmt::internal::CharTraits<char>::format_float(
1>                                       ^
1>spdlog\details/format.cc(453,41): error : redefinition of 'format_float'
1>  int fmt::internal::CharTraits<wchar_t>::format_float(
1>                                          ^
1>  spdlog\details/format.cc(453,41) :  note: previous definition is here
1>  int fmt::internal::CharTraits<wchar_t>::format_float(
1>                                          ^
1>spdlog\details/format.cc(467,41): error : redefinition of 'DIGITS'
1>  const char fmt::internal::BasicData<T>::DIGITS[] =
1>                                          ^
1>  spdlog\details/format.cc(467,41) :  note: previous definition is here
1>  const char fmt::internal::BasicData<T>::DIGITS[] =
1>                                          ^
1>CLANGCOMPILE : fatal error : too many errors emitted, stopping now [-ferror-limit=]
1>  4 warnings and 20 errors generated.
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

[vitaut]

The pragma issue have been fixed in fmtlib/fmt#256 but spdlog needs to update its copy of cppformat.

Not sure what redefinition errors are about, maybe format.cc is included multiple times somehow?

[LukeMauldin]

I pulled the latest format.h and format.cc from cppformat and replaced the ones in the spdlog master and in Visual Studio I set format.cc to not be included in the build. After doing those two steps, spdlog builds correctly with Visual Studio 2015 Clang. Can I recommend that spdlog updates its bundled copy of the cppformat library and adds a note to the README to set the format.cc file to not be included in the Visual Studio build?

[gabime]

updated spdlog to latest version of cppformat