--- format.h	2020-02-09 20:52:31.892811631 +0100
+++ 0ad/source/third_party/fmt/format.h	2020-03-04 21:53:39.475417249 +0100
@@ -1,4 +1,9 @@
 /*
+ * Slightly modified version of fmt, by Wildfire Games, for 0 A.D.
+ * Based on fmt v1.1.0 from https://github.com/fmtlib/fmt
+ */
+
+/*
  Formatting library for C++
 
  Copyright (c) 2012 - 2015, Victor Zverovich
@@ -37,10 +42,11 @@
 #include <algorithm>
 #include <limits>
 #include <stdexcept>
-#include <string>
 #include <sstream>
 
-#if _SECURE_SCL
+#include "ps/CStr.h"
+
+#if defined(_SECURE_SCL) && _SECURE_SCL
 # include <iterator>
 #endif
 
@@ -129,9 +135,13 @@
 // Variadic templates are available in GCC since version 4.4
 // (http://gcc.gnu.org/projects/cxx0x.html) and in Visual C++
 // since version 2013.
+# if defined(_MSC_VER)
+#  define FMT_USE_VARIADIC_TEMPLATES 1
+# else
 # define FMT_USE_VARIADIC_TEMPLATES \
    (FMT_HAS_FEATURE(cxx_variadic_templates) || \
-       (FMT_GCC_VERSION >= 404 && FMT_HAS_GXX_CXX11) || _MSC_VER >= 1800)
+       (FMT_GCC_VERSION >= 404 && FMT_HAS_GXX_CXX11))
+# endif
 #endif
 
 #ifndef FMT_USE_RVALUE_REFERENCES
@@ -139,10 +149,12 @@
 // as the latter doesn't provide std::move.
 # if defined(FMT_GNUC_LIBSTD_VERSION) && FMT_GNUC_LIBSTD_VERSION <= 402
 #  define FMT_USE_RVALUE_REFERENCES 0
+# elif defined(_MSC_VER)
+#  define FMT_USE_RVALUE_REFERENCES 1
 # else
 #  define FMT_USE_RVALUE_REFERENCES \
     (FMT_HAS_FEATURE(cxx_rvalue_references) || \
-        (FMT_GCC_VERSION >= 403 && FMT_HAS_GXX_CXX11) || _MSC_VER >= 1600)
+        (FMT_GCC_VERSION >= 403 && FMT_HAS_GXX_CXX11))
 # endif
 #endif
 
@@ -151,7 +163,7 @@
 #endif
 
 // Define FMT_USE_NOEXCEPT to make C++ Format use noexcept (C++11 feature).
-#if FMT_USE_NOEXCEPT || FMT_HAS_FEATURE(cxx_noexcept) || \
+#if (defined(FMT_USE_NOEXCEPT) && FMT_USE_NOEXCEPT) || FMT_HAS_FEATURE(cxx_noexcept) || \
   (FMT_GCC_VERSION >= 408 && FMT_HAS_GXX_CXX11)
 # define FMT_NOEXCEPT noexcept
 #else
@@ -160,7 +172,7 @@
 
 // A macro to disallow the copy constructor and operator= functions
 // This should be used in the private: declarations for a class
-#if FMT_USE_DELETED_FUNCTIONS || FMT_HAS_FEATURE(cxx_deleted_functions) || \
+#if (defined(FMT_USE_DELETED_FUNCTIONS) && FMT_USE_DELETED_FUNCTIONS) || FMT_HAS_FEATURE(cxx_deleted_functions) || \
   (FMT_GCC_VERSION >= 404 && FMT_HAS_GXX_CXX11) || _MSC_VER >= 1800
 # define FMT_DISALLOW_COPY_AND_ASSIGN(TypeName) \
     TypeName(const TypeName&) = delete; \
@@ -287,7 +299,7 @@
 // to avoid dynamic memory allocation.
 enum { INLINE_BUFFER_SIZE = 500 };
 
-#if _SECURE_SCL
+#if defined(_SECURE_SCL) && _SECURE_SCL
 // Use checked iterator to avoid warnings on MSVC.
 template <typename T>
 inline stdext::checked_array_iterator<T*> make_ptr(T *ptr, std::size_t size) {
@@ -483,7 +495,7 @@
 template <typename Char>
 class BasicCharTraits {
  public:
-#if _SECURE_SCL
+#if defined(_SECURE_SCL) && _SECURE_SCL
   typedef stdext::checked_array_iterator<Char*> CharPtr;
 #else
   typedef Char *CharPtr;
@@ -869,6 +881,7 @@
   FMT_MAKE_VALUE(const unsigned char *, ustring.value, CSTRING)
   FMT_MAKE_STR_VALUE(const std::string &, STRING)
   FMT_MAKE_STR_VALUE(StringRef, STRING)
+  FMT_MAKE_STR_VALUE(const CStr &, STRING)
 
 #define FMT_MAKE_WSTR_VALUE(Type, TYPE) \
   MakeValue(typename WCharHelper<Type, Char>::Supported value) { \
@@ -1567,7 +1580,7 @@
 
   typedef typename internal::CharTraits<Char>::CharPtr CharPtr;
 
-#if _SECURE_SCL
+#if defined(_SECURE_SCL) && _SECURE_SCL
   // Returns pointer value.
   static Char *get(CharPtr p) { return p.base(); }
 #else
@@ -2074,7 +2087,7 @@
   Char fill = static_cast<Char>(spec.fill());
   for (;;) {
     std::size_t buffer_size = buffer_.capacity() - offset;
-#if _MSC_VER
+#if defined(_MSC_VER) && _MSC_VER
     // MSVC's vsnprintf_s doesn't work with zero size, so reserve
     // space for at least one extra character to make the size non-zero.
     // Note that the buffer's capacity will increase by more than 1.
--- format.cpp	2020-02-09 20:52:10.936425878 +0100
+++ 0ad/source/third_party/fmt/format.cpp	2020-03-04 21:36:15.755684084 +0100
@@ -1,4 +1,9 @@
 /*
+ * Slightly modified version of fmt, by Wildfire Games, for 0 A.D.
+ * Based on fmt v1.1.0 from https://github.com/fmtlib/fmt
+ */
+
+/*
  Formatting library for C++
 
  Copyright (c) 2012 - 2015, Victor Zverovich
@@ -24,6 +29,7 @@
  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
+#include "precompiled.h"
 
 #include "format.h"
 
@@ -48,7 +54,7 @@
 #if __GNUC__ && !__EXCEPTIONS
 # define FMT_EXCEPTIONS 0
 #endif
-#if _MSC_VER && !_HAS_EXCEPTIONS
+#if defined(_MSC_VER) && _MSC_VER && !_HAS_EXCEPTIONS
 # define FMT_EXCEPTIONS 0
 #endif
 #ifndef FMT_EXCEPTIONS
@@ -79,17 +85,17 @@
 # define FMT_FUNC
 #endif
 
-#if _MSC_VER
-# pragma warning(push)
-# pragma warning(disable: 4127)  // conditional expression is constant
-# pragma warning(disable: 4702)  // unreachable code
-#endif
-
 namespace {
 
 #ifndef _MSC_VER
 # define FMT_SNPRINTF snprintf
 #else  // _MSC_VER
+
+# pragma warning(push)
+# pragma warning(disable: 4127) // conditional expression is constant
+# pragma warning(disable: 4702) // unreachable code
+# pragma warning(disable: 4456) // hides previous local declaration
+
 inline int fmt_snprintf(char *buffer, size_t size, const char *format, ...) {
   va_list args;
   va_start(args, format);
@@ -136,24 +142,24 @@
     int error_code, char *&buffer, std::size_t buffer_size) FMT_NOEXCEPT {
   assert(buffer != 0 && buffer_size != 0);
   int result = 0;
-#if ((_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600) && !_GNU_SOURCE) || __ANDROID__
+#if ((_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600) && !_GNU_SOURCE) || (defined(__ANDROID__) && __ANDROID__)
   // XSI-compliant version of strerror_r.
   result = strerror_r(error_code, buffer, buffer_size);
   if (result != 0)
     result = errno;
-#elif _GNU_SOURCE
+#elif defined(_GNU_SOURCE) && !defined(__BIONIC__)
   // GNU-specific version of strerror_r.
   char *message = strerror_r(error_code, buffer, buffer_size);
   // If the buffer is full then the message is probably truncated.
   if (message == buffer && strlen(buffer) == buffer_size - 1)
     result = ERANGE;
   buffer = message;
-#elif __MINGW32__
+#elif defined(__MINGW32__)
   errno = 0;
   (void)buffer_size;
   buffer = strerror(error_code);
   result = errno;
-#elif _WIN32
+#elif defined(_WIN32)
   result = strerror_s(buffer, buffer_size, error_code);
   // If the buffer is full then the message is probably truncated.
   if (result == 0 && std::strlen(buffer) == buffer_size - 1)
@@ -627,8 +633,11 @@
   const StrChar *str_value = s.value;
   std::size_t str_size = s.size;
   if (str_size == 0) {
-    if (!str_value)
-      FMT_THROW(FormatError("string pointer is null"));
+    if (!str_value) {
+        Char err[] = { '(', 'n', 'u', 'l', 'l', ')' };
+        write_str(err, sizeof(err)/sizeof(Char), spec);
+        return;
+    }
     if (*str_value)
       str_size = std::char_traits<StrChar>::length(str_value);
   }
@@ -1164,6 +1173,6 @@
 
 #endif  // FMT_HEADER_ONLY
 
-#if _MSC_VER
+#if defined(_MSC_VER) && _MSC_VER
 # pragma warning(pop)
 #endif