From 8487860a8c634bdbaee6056c2081d147041c3b06 Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <sezeroz@gmail.com>
Date: Wed, 6 Mar 2024 01:11:55 +0300
Subject: [PATCH] windows exports: use dllexport attribute, instead of
 visibility.

With older toolchains, at the least, visibility attributes don't
work and all symbols are exported along with lots of unsupported
warnings.

Change-Id: I6ffe220b7589a6bda00f42c17ead35592de7cc5a
---
 CMakeLists.txt      |  4 +++-
 configure.ac        |  3 ++-
 sharpyuv/sharpyuv.h | 10 ++++------
 src/webp/types.h    | 12 +++++-------
 4 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index cfc625ed..bce1a7f3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -135,7 +135,7 @@ if(WEBP_UNICODE)
   add_definitions(-DUNICODE -D_UNICODE)
 endif()
 
-if(MSVC AND BUILD_SHARED_LIBS)
+if(WIN32 AND BUILD_SHARED_LIBS)
   add_definitions(-DWEBP_DLL)
 endif()
 
@@ -163,7 +163,9 @@ if(MSVC)
   set(CMAKE_STATIC_LIBRARY_PREFIX "${webp_libname_prefix}")
 endif()
 
+if(NOT WIN32)
 set(CMAKE_C_VISIBILITY_PRESET hidden)
+endif()
 
 if(WEBP_ENABLE_WUNUSED_RESULT)
   if(CMAKE_VERSION VERSION_GREATER_EQUAL 3.21.0)
diff --git a/configure.ac b/configure.ac
index 128c3633..53753a67 100644
--- a/configure.ac
+++ b/configure.ac
@@ -763,7 +763,8 @@ AC_CONFIG_FILES([Makefile src/Makefile man/Makefile \
                  src/libwebp.pc src/libwebpdecoder.pc \
                  src/demux/libwebpdemux.pc src/mux/libwebpmux.pc])
 
-
+dnl fix exports from MinGW builds
+AC_CONFIG_COMMANDS_POST([$SED -i 's/-DDLL_EXPORT/-DWEBP_DLL/' config.status])
 AC_OUTPUT
 
 AC_MSG_NOTICE([
diff --git a/sharpyuv/sharpyuv.h b/sharpyuv/sharpyuv.h
index 23a69ce3..fe958915 100644
--- a/sharpyuv/sharpyuv.h
+++ b/sharpyuv/sharpyuv.h
@@ -22,15 +22,13 @@ extern "C" {
 #else
 // This explicitly marks library functions and allows for changing the
 // signature for e.g., Windows DLL builds.
-#if defined(__GNUC__) && __GNUC__ >= 4
+#if defined(_WIN32) && defined(WEBP_DLL)
+#define SHARPYUV_EXTERN __declspec(dllexport)
+#elif defined(__GNUC__) && __GNUC__ >= 4
 #define SHARPYUV_EXTERN extern __attribute__((visibility("default")))
 #else
-#if defined(_MSC_VER) && defined(WEBP_DLL)
-#define SHARPYUV_EXTERN __declspec(dllexport)
-#else
 #define SHARPYUV_EXTERN extern
-#endif /* _MSC_VER && WEBP_DLL */
-#endif /* __GNUC__ >= 4 */
+#endif /* defined(_WIN32) && defined(WEBP_DLL) */
 #endif /* WEBP_EXTERN */
 #endif /* SHARPYUV_EXTERN */
 
diff --git a/src/webp/types.h b/src/webp/types.h
index f1727491..0e7ef129 100644
--- a/src/webp/types.h
+++ b/src/webp/types.h
@@ -56,15 +56,13 @@ typedef long long int int64_t;
 #ifndef WEBP_EXTERN
 // This explicitly marks library functions and allows for changing the
 // signature for e.g., Windows DLL builds.
-# if defined(__GNUC__) && __GNUC__ >= 4
+# if defined(_WIN32) && defined(WEBP_DLL)
+#  define WEBP_EXTERN __declspec(dllexport)
+# elif defined(__GNUC__) && __GNUC__ >= 4
 #  define WEBP_EXTERN extern __attribute__ ((visibility ("default")))
 # else
-#  if defined(_MSC_VER) && defined(WEBP_DLL)
-#   define WEBP_EXTERN __declspec(dllexport)
-#  else
-#   define WEBP_EXTERN extern
-#  endif
-# endif  /* __GNUC__ >= 4 */
+#  define WEBP_EXTERN extern
+# endif  /* defined(_WIN32) && defined(WEBP_DLL) */
 #endif  /* WEBP_EXTERN */
 
 // Macro to check ABI compatibility (same major revision number)