This enables building the library under Visual Studio 2015 (#1002)

Co-authored-by: Daniel Lemire <lemire@gmai.com>

.appveyor.yml

@@ -20,6 +20,10 @@ environment:
       platform: Win32
       CMAKE_ARGS:  -A %Platform% -DSIMDJSON_BUILD_STATIC=OFF -DSIMDJSON_ENABLE_THREADS=ON # This should be the default. Testing anyway.
       CTEST_ARGS: -E checkperf
+    - job_name: VS2015
+      image: Visual Studio 2015
+      CMAKE_ARGS:  -A %Platform% -DSIMDJSON_BUILD_STATIC=ON -DSIMDJSON_ENABLE_THREADS=OFF
+      CTEST_ARGS: -E checkperf
 
 build_script:
   - mkdir build

cmake/simdjson-flags.cmake

@@ -74,7 +74,13 @@ set(THREADS_PREFER_PTHREAD_FLAG ON)
 
 
 if(MSVC)
+if(${CMAKE_VS_PLATFORM_TOOLSET} STREQUAL "v140")
+  # Visual Studio 2015 issues warnings and we tolerate it,  cmake -G"Visual Studio 14" ..
+  target_compile_options(simdjson-internal-flags INTERFACE /W0 /sdl)
+else()
+  # Recent version of Visual Studio expected (2017, 2019...). Prior versions are unsupported.
   target_compile_options(simdjson-internal-flags INTERFACE /WX /W3 /sdl)
+endif()
 else()
   target_compile_options(simdjson-internal-flags INTERFACE -fPIC)
   target_compile_options(simdjson-internal-flags INTERFACE -Werror -Wall -Wextra -Weffc++)

include/simdjson/common_defs.h

@@ -81,12 +81,15 @@ constexpr size_t DEFAULT_MAX_DEPTH = 1024;
   #define SIMDJSON_PUSH_DISABLE_ALL_WARNINGS __pragma(warning( push, 0 ))
   #define SIMDJSON_DISABLE_VS_WARNING(WARNING_NUMBER) __pragma(warning( disable : WARNING_NUMBER ))
   // Get rid of Intellisense-only warnings (Code Analysis)
-  // Though __has_include is C++17, it looks like it is supported in Visual Studio 2017 or better.
-  // We are probably not supporting earlier version of Visual Studio in any case.
+  // Though __has_include is C++17, it is supported in Visual Studio 2017 or better (_MSC_VER>=1910).
+  #if defined(_MSC_VER) && (_MSC_VER>=1910) 
   #if __has_include(<CppCoreCheck\Warnings.h>)
   #include <CppCoreCheck\Warnings.h>
   #define SIMDJSON_DISABLE_UNDESIRED_WARNINGS SIMDJSON_DISABLE_VS_WARNING(ALL_CPPCORECHECK_WARNINGS)
-  #else
+  #endif
+  #endif
+
+  #ifndef SIMDJSON_DISABLE_UNDESIRED_WARNINGS
   #define SIMDJSON_DISABLE_UNDESIRED_WARNINGS
   #endif
 

include/simdjson/dom/parser.h

@@ -391,7 +391,12 @@ private:
   /**
    * The loaded buffer (reused each time load() is called)
    */
+  #if defined(_MSC_VER) && _MSC_VER < 1910
+  // older versions of Visual Studio lack proper support for unique_ptr.
+  std::unique_ptr<char[]> loaded_bytes;
+  #else
   std::unique_ptr<char[], decltype(&aligned_free_char)> loaded_bytes;
+  #endif
 
   /** Capacity of loaded_bytes buffer. */
   size_t _loaded_bytes_capacity{0};

include/simdjson/inline/padded_string.h

@@ -21,7 +21,12 @@ inline char *allocate_padded_buffer(size_t length) noexcept {
   // return (char *) malloc(length + SIMDJSON_PADDING);
   // However, we might as well align to cache lines...
   size_t totalpaddedlength = length + SIMDJSON_PADDING;
+#if defined(_MSC_VER) && _MSC_VER < 1910
+  // For legacy Visual Studio 2015 since it does not have proper C++11 support
+  char *padded_buffer = new[totalpaddedlength];
+#else
   char *padded_buffer = aligned_malloc_char(64, totalpaddedlength);
+#endif
 #ifndef NDEBUG
   if (padded_buffer == nullptr) {
     return nullptr;

include/simdjson/inline/parser.h

@@ -15,10 +15,18 @@ namespace dom {
 //
 // parser inline implementation
 //
+#if defined(_MSC_VER) && _MSC_VER < 1910
+// older versions of Visual Studio lack proper support for unique_ptr.
+really_inline parser::parser(size_t max_capacity) noexcept
+  : _max_capacity{max_capacity},
+    loaded_bytes(nullptr) {
+}
+#else 
 really_inline parser::parser(size_t max_capacity) noexcept
   : _max_capacity{max_capacity},
     loaded_bytes(nullptr, &aligned_free_char) {
 }
+#endif
 really_inline parser::parser(parser &&other) noexcept = default;
 really_inline parser &parser::operator=(parser &&other) noexcept = default;
 

include/simdjson/portability.h

@@ -5,7 +5,7 @@
 #include <cstdint>
 #include <cstdlib>
 #include <cfloat>
-
+#include <cassert>
 
 #ifdef _MSC_VER
 #define SIMDJSON_VISUAL_STUDIO 1
@@ -232,7 +232,6 @@ static inline void aligned_free_char(char *mem_block) {
 
 #else // NDEBUG
 
-#include <cassert>
 #define SIMDJSON_UNREACHABLE() assert(0);
 #define SIMDJSON_ASSUME(COND) assert(COND)
 

singleheader/amalgamate_demo.cpp

@@ -1,4 +1,4 @@
-/* auto-generated on Sun 28 Jun 2020 12:39:28 EDT. Do not edit! */
+/* auto-generated on Sun 28 Jun 2020 20:08:45 EDT. Do not edit! */
 
 #include <iostream>
 #include "simdjson.h"

singleheader/simdjson.cpp

@@ -1,4 +1,4 @@
-/* auto-generated on Sun 28 Jun 2020 12:39:28 EDT. Do not edit! */
+/* auto-generated on Sun 28 Jun 2020 20:08:45 EDT. Do not edit! */
 /* begin file src/simdjson.cpp */
 #include "simdjson.h"
 

singleheader/simdjson.h

@@ -1,4 +1,4 @@
-/* auto-generated on Sun 28 Jun 2020 12:39:28 EDT. Do not edit! */
+/* auto-generated on Sun 28 Jun 2020 20:08:45 EDT. Do not edit! */
 /* begin file include/simdjson.h */
 #ifndef SIMDJSON_H
 #define SIMDJSON_H
@@ -59,7 +59,7 @@
 #include <cstdint>
 #include <cstdlib>
 #include <cfloat>
-
+#include <cassert>
 
 #ifdef _MSC_VER
 #define SIMDJSON_VISUAL_STUDIO 1
@@ -286,7 +286,6 @@ static inline void aligned_free_char(char *mem_block) {
 
 #else // NDEBUG
 
-#include <cassert>
 #define SIMDJSON_UNREACHABLE() assert(0);
 #define SIMDJSON_ASSUME(COND) assert(COND)
 
@@ -373,12 +372,15 @@ constexpr size_t DEFAULT_MAX_DEPTH = 1024;
   #define SIMDJSON_PUSH_DISABLE_ALL_WARNINGS __pragma(warning( push, 0 ))
   #define SIMDJSON_DISABLE_VS_WARNING(WARNING_NUMBER) __pragma(warning( disable : WARNING_NUMBER ))
   // Get rid of Intellisense-only warnings (Code Analysis)
-  // Though __has_include is C++17, it looks like it is supported in Visual Studio 2017 or better.
-  // We are probably not supporting earlier version of Visual Studio in any case.
+  // Though __has_include is C++17, it is supported in Visual Studio 2017 or better (_MSC_VER>=1910).
+  #if defined(_MSC_VER) && (_MSC_VER>=1910) 
   #if __has_include(<CppCoreCheck\Warnings.h>)
   #include <CppCoreCheck\Warnings.h>
   #define SIMDJSON_DISABLE_UNDESIRED_WARNINGS SIMDJSON_DISABLE_VS_WARNING(ALL_CPPCORECHECK_WARNINGS)
-  #else
+  #endif
+  #endif
+
+  #ifndef SIMDJSON_DISABLE_UNDESIRED_WARNINGS
   #define SIMDJSON_DISABLE_UNDESIRED_WARNINGS
   #endif
 
@@ -3673,7 +3675,12 @@ private:
   /**
    * The loaded buffer (reused each time load() is called)
    */
+  #if defined(_MSC_VER) && _MSC_VER < 1910
+  // older versions of Visual Studio lack proper support for unique_ptr.
+  std::unique_ptr<char[]> loaded_bytes;
+  #else
   std::unique_ptr<char[], decltype(&aligned_free_char)> loaded_bytes;
+  #endif
 
   /** Capacity of loaded_bytes buffer. */
   size_t _loaded_bytes_capacity{0};
@@ -6779,7 +6786,12 @@ inline char *allocate_padded_buffer(size_t length) noexcept {
   // return (char *) malloc(length + SIMDJSON_PADDING);
   // However, we might as well align to cache lines...
   size_t totalpaddedlength = length + SIMDJSON_PADDING;
+#if defined(_MSC_VER) && _MSC_VER < 1910
+  // For legacy Visual Studio 2015 since it does not have proper C++11 support
+  char *padded_buffer = new[totalpaddedlength];
+#else
   char *padded_buffer = aligned_malloc_char(64, totalpaddedlength);
+#endif
 #ifndef NDEBUG
   if (padded_buffer == nullptr) {
     return nullptr;
@@ -7401,10 +7413,18 @@ namespace dom {
 //
 // parser inline implementation
 //
+#if defined(_MSC_VER) && _MSC_VER < 1910
+// older versions of Visual Studio lack proper support for unique_ptr.
+really_inline parser::parser(size_t max_capacity) noexcept
+  : _max_capacity{max_capacity},
+    loaded_bytes(nullptr) {
+}
+#else 
 really_inline parser::parser(size_t max_capacity) noexcept
   : _max_capacity{max_capacity},
     loaded_bytes(nullptr, &aligned_free_char) {
 }
+#endif
 really_inline parser::parser(parser &&other) noexcept = default;
 really_inline parser &parser::operator=(parser &&other) noexcept = default;