make my windows cross-compiler (gcc 7.2 from mxe) shut the fuck up

CMakeLists.txt

@@ -126,6 +126,7 @@ option(USE_AUDIO "Build with audio support (SDL2_mixer)." ON)
 option(USE_ZIP "Build with .zip package support." ON)
 option(USE_CPACK "Add a 'package' target, used to prepare a release for binary distribution. Currently only used to create Windows installers. Requires CPack and NSIS." OFF)
 option(USE_COTIRE "Use cotire (COmpile TIme REducer) to speed up builds." OFF)
+option(USE_INTEL_INTRIN "Use some x86-specific intrinsics for optimizations where appropriate (if possible). Note that this is not equivalent to e.g. supplying -march in CFLAGS." ON)
 option(DEBUG_USE_UBSAN "Enable the Undefined Behaviour Sanitizer (UBSan) in debug builds. Only disable if the compiler or target platform doesn't support it." ON)
 option(DEBUG_USE_ASAN "Enable the Address Sanitizer (ASan) and leak detection in debug builds." OFF)
 option(RELWITHDEBINFO_USE_DEBUG_FLAGS "Use debug flags in RelWithDebInfo builds (e.g. sanitizers)." OFF)

src/CMakeLists.txt

@@ -28,19 +28,17 @@ check_symbol_exists(__STDC_NO_COMPLEX__ "unistd.h" COMPLEX_MISSING)
 check_symbol_exists(__STDC_NO_VLA__ "unistd.h" VLA_MISSING)
 
 # This doesn't work on gcc...
-# check_symbol_exists(_mm_crc32_u8 "immintrin.h" HAVE_CRC32_INTRIN)
+# check_symbol_exists(_mm_crc32_u8 "immintrin.h" HAVE_INTEL_INTRIN)
+
+unset(HAVE_INTEL_INTRIN CACHE)
 
 check_c_source_compiles("
 #include <immintrin.h>
 __attribute__((target(\"sse4.2\")))
 int main(int argc, char **argv) {
-	return _mm_crc32_u8(0, 42);
+	return _mm_crc32_u8(argc, 42);
 }
-" HAVE_CRC32_INTRIN)
-
-if(HAVE_CRC32_INTRIN)
-	add_definitions(-DHAVE_CRC32_INTRIN)
-endif()
+" HAVE_INTEL_INTRIN)
 
 if(COMPLEX_MISSING OR VLA_MISSING)
 	message(FATAL_ERROR "Your C implementation needs to support complex numbers and variable length arrays.")
@@ -144,15 +142,24 @@ set(SRCs
 	"${CMAKE_CURRENT_BINARY_DIR}/version_auto.c"
 )
 
+if(USE_INTEL_INTRIN AND HAVE_INTEL_INTRIN)
+	set(SRCs ${SRCs}
+		util_sse42.c
+	)
+	add_definitions(-DHAVE_INTEL_INTRIN)
+	set_property(SOURCE util_sse42.c APPEND_STRING PROPERTY COMPILE_FLAGS "-msse4.2")
+endif()
+
 if(USE_ZIP AND ZIP_SUPPORTED)
 	set(SRCs ${SRCs}
 		rwops/rwops_zipfile.c
 		vfs/zipfile.c
-		vfs/zippath.c)
+		vfs/zippath.c
+	)
 else()
 	set(SRCs ${SRCs}
 		vfs/zipfile_null.c
-		)
+	)
 endif()
 
 if(WIN32)

src/compat.h

@@ -21,5 +21,3 @@
 #else
     #define FORMAT_ATTR printf
 #endif
-
-void shut_up_stupid_warning(void);

src/util.c

@@ -709,20 +709,6 @@ uint32_t crc32str(uint32_t crc, const char *str) {
     return crc ^ ~0U;
 }
 
-#ifdef HAVE_CRC32_INTRIN
-#include <immintrin.h>
-__attribute__((target("sse4.2")))
-uint32_t crc32str_sse42(uint32_t crc, const char *str) {
-    const uint8_t *s = (const uint8_t*)str;
-
-    while(*s) {
-        crc = _mm_crc32_u8(crc, *s++);
-    }
-
-    return crc;
-}
-#endif
-
 #ifdef DEBUG
 
 bool _in_draw_code;

src/util.h

@@ -15,6 +15,7 @@
 #include <zlib.h> // compiling under mingw may fail without this...
 #include <png.h>
 #include <SDL.h>
+#include "util_sse42.h"
 #include "hashtable.h"
 #include "vfs/public.h"
 #include "log.h"
@@ -139,10 +140,6 @@ int getenvint(const char *v, int defaultval) __attribute__((pure));
 void png_setup_error_handlers(png_structp png);
 uint32_t crc32str(uint32_t crc, const char *str) __attribute__((hot, pure));
 
-#if defined(HAVE_CRC32_INTRIN) && defined(DISABLE_CRC32_INTRIN)
-#undef HAVE_CRC32_INTRIN
-#endif
-
 #ifdef HAVE_CRC32_INTRIN
 uint32_t crc32str_sse42(uint32_t crc, const char *str) __attribute__((hot, pure));
 #else
@@ -152,6 +149,9 @@ uint32_t crc32str_sse42(uint32_t crc, const char *str) __attribute__((hot, pure)
 noreturn void _ts_assert_fail(const char *cond, const char *func, const char *file, int line, bool use_log);
 
 #undef assert
+#undef static_assert
+
+#define static_assert _Static_assert
 
 #ifdef NDEBUG
     #define _assert(cond,uselog)

src/util_sse42.c

@@ -0,0 +1,21 @@
+/*
+ * This software is licensed under the terms of the MIT-License
+ * See COPYING for further information.
+ * ---
+ * Copyright (c) 2011-2017, Lukas Weber <laochailan@web.de>.
+ * Copyright (c) 2012-2017, Andrei Alexeyev <akari@alienslab.net>.
+ */
+
+#include <immintrin.h>
+#include "util_sse42.h"
+
+__attribute__((target("sse4.2")))
+uint32_t crc32str_sse42(uint32_t crc, const char *str) {
+    const uint8_t *s = (const uint8_t*)str;
+
+    while(*s) {
+        crc = _mm_crc32_u8(crc, *s++);
+    }
+
+    return crc;
+}

src/util_sse42.h

@@ -0,0 +1,18 @@
+/*
+ * This software is licensed under the terms of the MIT-License
+ * See COPYING for further information.
+ * ---
+ * Copyright (c) 2011-2017, Lukas Weber <laochailan@web.de>.
+ * Copyright (c) 2012-2017, Andrei Alexeyev <akari@alienslab.net>.
+ */
+
+#pragma once
+
+#include <stdint.h>
+#include "compat.h"
+
+#ifdef HAVE_INTEL_INTRIN
+    uint32_t crc32str_sse42(uint32_t crc, const char *str) __attribute__((hot, pure));
+#else
+    #define crc32str_sse42 crc32str
+#endif