mingw-w64-gtk2: Fix GCC 10 build

Fix multiple definition of `gdk_threads_mutex' and undefined reference to
'IID_IUnknown' when building with GCC 10.

https://gitlab.gnome.org/GNOME/gtk/-/issues/2958
https://gitlab.gnome.org/GNOME/gtk/-/merge_requests/2305
https://gitlab.gnome.org/GNOME/gtk/-/issues/3029
https://gitlab.gnome.org/GNOME/gtk/-/merge_requests/2481

4 files changed, 198 insertions, 7 deletions

diff --git a/.SRCINFO b/.SRCINFO
index 817e0e63f959..e4bc0c711f34 100644
--- a/.SRCINFO
+++ b/.SRCINFO
@@ -1,9 +1,7 @@
-# Generated by mksrcinfo v8
-# Wed Jan 10 12:59:54 UTC 2018
 pkgbase = mingw-w64-gtk2
 	pkgdesc = GObject-based multi-platform GUI toolkit (legacy) (mingw-w64)
 	pkgver = 2.24.32
-	pkgrel = 1
+	pkgrel = 2
 	url = http://www.gtk.org
 	arch = any
 	license = LGPL
@@ -22,7 +20,11 @@ pkgbase = mingw-w64-gtk2
 	options = !buildflags
 	options = staticlibs
 	source = https://download.gnome.org/sources/gtk+/2.24/gtk+-2.24.32.tar.xz
+	source = gtk2-fix-gcc-10-build.patch
+	source = gtk2-fix-out-of-source-build.patch
 	sha256sums = b6c8a93ddda5eabe3bfee1eb39636c9a03d2a56c7b62828b359bf197943c582e
+	sha256sums = a3d347337b0aaa2b170b836c20070f758698949d0511b9a92528ab4926bdcfe6
+	sha256sums = e88bb004767c95cd567f225995891f054218e2c806844a3e5c12b70ac3ea231e
 
 pkgname = mingw-w64-gtk2
 
diff --git a/PKGBUILD b/PKGBUILD
index 5855db69dcfd..fa17f65e004b 100644
--- a/PKGBUILD
+++ b/PKGBUILD
@@ -1,6 +1,6 @@
 pkgname=mingw-w64-gtk2
 pkgver=2.24.32
-pkgrel=1
+pkgrel=2
 pkgdesc="GObject-based multi-platform GUI toolkit (legacy) (mingw-w64)"
 arch=('any')
 url="http://www.gtk.org"
@@ -19,16 +19,35 @@ depends=(
   'mingw-w64-cairo>=1.6'
   'mingw-w64-gdk-pixbuf2>=2.21.0')
 options=('!strip' '!buildflags' 'staticlibs')
-source=("https://download.gnome.org/sources/gtk+/${pkgver%.*}/gtk+-${pkgver}.tar.xz")
-sha256sums=("b6c8a93ddda5eabe3bfee1eb39636c9a03d2a56c7b62828b359bf197943c582e")
+source=(
+  "https://download.gnome.org/sources/gtk+/${pkgver%.*}/gtk+-${pkgver}.tar.xz"
+  'gtk2-fix-gcc-10-build.patch'
+  'gtk2-fix-out-of-source-build.patch')
+sha256sums=(
+  'b6c8a93ddda5eabe3bfee1eb39636c9a03d2a56c7b62828b359bf197943c582e'
+  'a3d347337b0aaa2b170b836c20070f758698949d0511b9a92528ab4926bdcfe6'
+  'e88bb004767c95cd567f225995891f054218e2c806844a3e5c12b70ac3ea231e')
 
 _architectures=('i686-w64-mingw32' 'x86_64-w64-mingw32')
 
+prepare() {
+  cd "${srcdir}/gtk+-${pkgver}"
+  local source_file
+  for source_file in "${source[@]}"; do
+    case "${source_file}" in
+      *.patch)
+        patch -p1 < "${srcdir}/${source_file}"
+        ;;
+    esac
+  done
+  rm "${srcdir}/gtk+-${pkgver}/gtk/gtk.def"
+}
+
 build() {
   cd "${srcdir}/gtk+-${pkgver}"
+  autoreconf -fi
   for _arch in "${_architectures[@]}"; do
     msg "Building for ${_arch}"
-    rm "${srcdir}/gtk+-${pkgver}/gtk/gtk.def"
     mkdir -p "build-${_arch}"
     cd "build-${_arch}"
     msg "Starting configure and make"
diff --git a/gtk2-fix-gcc-10-build.patch b/gtk2-fix-gcc-10-build.patch
new file mode 100644
index 000000000000..8cb040b8676d
--- /dev/null
+++ b/gtk2-fix-gcc-10-build.patch
@@ -0,0 +1,72 @@
+From aae860fe3e9f25526a40734a01fa6eadefbe26e6 Mon Sep 17 00:00:00 2001
+From: Philip Zander <philip.zander@gmail.com>
+Date: Tue, 28 Jul 2020 02:31:52 +0200
+Subject: [PATCH] Change  `__declspec(dllexport)` to `extern
+ __declspec(dllexport)`
+
+As of 28 July 2020, building on MSYS2 fails with "multiple definition"
+errors unless exported variables are explicitly marked as "extern".
+
+Closes #2958
+---
+ gdk/gdktypes.h     | 2 +-
+ gtk/gtkdebug.h     | 2 +-
+ gtk/gtkmain.h      | 2 +-
+ gtk/gtktexttypes.h | 2 +-
+ 4 files changed, 4 insertions(+), 4 deletions(-)
+
+diff --git a/gdk/gdktypes.h b/gdk/gdktypes.h
+index eed31243ba..c72b20b92e 100644
+--- a/gdk/gdktypes.h
++++ b/gdk/gdktypes.h
+@@ -39,7 +39,7 @@
+ 
+ #ifdef G_OS_WIN32
+ #  ifdef GDK_COMPILATION
+-#    define GDKVAR __declspec(dllexport)
++#    define GDKVAR extern __declspec(dllexport)
+ #  else
+ #    define GDKVAR extern __declspec(dllimport)
+ #  endif
+diff --git a/gtk/gtkdebug.h b/gtk/gtkdebug.h
+index 05964f8dbe..623750301d 100644
+--- a/gtk/gtkdebug.h
++++ b/gtk/gtkdebug.h
+@@ -64,7 +64,7 @@ typedef enum {
+ 
+ #ifdef G_OS_WIN32
+ #  ifdef GTK_COMPILATION
+-#    define GTKVAR __declspec(dllexport)
++#    define GTKVAR extern __declspec(dllexport)
+ #  else
+ #    define GTKVAR extern __declspec(dllimport)
+ #  endif
+diff --git a/gtk/gtkmain.h b/gtk/gtkmain.h
+index 02a1daea9e..2f057e5478 100644
+--- a/gtk/gtkmain.h
++++ b/gtk/gtkmain.h
+@@ -67,7 +67,7 @@ typedef gint	(*GtkKeySnoopFunc)	    (GtkWidget	  *grab_widget,
+  */
+ #ifdef G_PLATFORM_WIN32
+ #ifdef GTK_COMPILATION
+-#define GTKMAIN_C_VAR __declspec(dllexport)
++#define GTKMAIN_C_VAR extern __declspec(dllexport)
+ #else
+ #define GTKMAIN_C_VAR extern __declspec(dllimport)
+ #endif
+diff --git a/gtk/gtktexttypes.h b/gtk/gtktexttypes.h
+index c624aeaf3a..eb0db36e6d 100644
+--- a/gtk/gtktexttypes.h
++++ b/gtk/gtktexttypes.h
+@@ -44,7 +44,7 @@ typedef struct _GtkTextMarkBody GtkTextMarkBody;
+ 
+ #ifdef G_OS_WIN32
+ #ifdef GTK_COMPILATION
+-#define VARIABLE __declspec(dllexport)
++#define VARIABLE extern __declspec(dllexport)
+ #else
+ #define VARIABLE extern __declspec(dllimport)
+ #endif
+-- 
+GitLab
+
diff --git a/gtk2-fix-out-of-source-build.patch b/gtk2-fix-out-of-source-build.patch
new file mode 100644
index 000000000000..17e88caf4b10
--- /dev/null
+++ b/gtk2-fix-out-of-source-build.patch
@@ -0,0 +1,98 @@
+From f203b1a751accbc55526d2e49cddc90355718a4a Mon Sep 17 00:00:00 2001
+From: Ting-Wei Lan <lantw@src.gnome.org>
+Date: Wed, 26 Aug 2020 01:01:56 +0800
+Subject: [PATCH] build: Move gtk.def to builddir
+
+GTK2 uses different gtk.def files on 32-bit and 64-bit Windows. GTK2
+source tarballs ship pre-generated gtk.def for 32-bit Windows. If the
+user wants to build for 64-bit Windows, the pre-generated gtk.def must
+be deleted before the build to force regeneration, or it will fail to
+link with 'symbol not defined' errors because the 32-bit Windows build
+includes more legacy functions than the 64-bit Windows build.
+
+While users who want to build for 64-bit Windows can delete gtk.def in
+the build script, which is currently what most build scripts do, doing
+so breaks out-of-source build. On AUR, MinGW packages are usually built
+and packaged in the following order:
+
+1. Run 'configure' and 'make' to build for i686-w64-mingw32.
+2. Run 'configure' and 'make' to build for x86_64-w64-mingw32.
+3. Run 'make install' for i686-w64-mingw32.
+4. Run 'make install' for x86_64-w64-mingw32.
+
+It fails because step 3 sees gtk.def left by step 2, which is generated
+for a different build. In step 3, make sees the gtk.def change and runs
+libtool to relink libgtk-win32-2.0-0.dll. libtool fails to find a lot of
+necessary libraries, decides that it is not possible to build a DLL with
+-no-undefined, and produces only the static library. It then tries to
+relink executables with the static library, and fails with undefined
+reference to 'IID_IUnknown' because -Wl,--start-group isn't used and
+the use of -Wl,-luuid prevents libtool from using the correct order.
+
+To resolve the problem, move gtk.def to builddir so different builds can
+have different gtk.def files while sharing the same source tree. This
+also means that the source tarball will no longer include pre-generated
+gtk.def file, which should be acceptable because it is already broken on
+64-bit Windows.
+
+Fixes https://gitlab.gnome.org/GNOME/gtk/-/issues/3029
+---
+ gtk/Makefile.am | 13 ++++++-------
+ 1 file changed, 6 insertions(+), 7 deletions(-)
+
+diff --git a/gtk/Makefile.am b/gtk/Makefile.am
+index cdbbd8c8d9..5b337da644 100644
+--- a/gtk/Makefile.am
++++ b/gtk/Makefile.am
+@@ -71,7 +71,7 @@ endif
+ 
+ if OS_WIN32
+ gtk_def = gtk.def
+-gtk_win32_symbols = -export-symbols $(srcdir)/gtk.def
++gtk_win32_symbols = -export-symbols gtk.def
+ 
+ gtk_win32_res = gtk-win32-res.o
+ gtk_win32_res_ldflag = -Wl,gtk-win32-res.o
+@@ -81,7 +81,7 @@ gtk-win32-res.o : gtk-win32.rc
+ 
+ install-def-file: gtk.def
+ 	$(mkinstalldirs) $(DESTDIR)$(libdir)
+-	$(INSTALL) $(srcdir)/gtk.def $(DESTDIR)$(libdir)/gtk-win32-2.0.def
++	$(INSTALL) gtk.def $(DESTDIR)$(libdir)/gtk-win32-2.0.def
+ uninstall-def-file:
+ 	-rm $(DESTDIR)$(libdir)/gtk-win32-2.0.def
+ else
+@@ -106,10 +106,10 @@ install-ms-lib:
+ uninstall-ms-lib:
+ endif
+ 
+-# This places the generated .def file in srcdir, since it is expected to be there.
+-# (The one from a tarball is)
++# gtk.def has to be put in builddir and should not be included in a source
++# tarball because it differs in 32-bit and 64-bit Windows builds.
+ gtk.def: gtk.symbols
+-	(echo -e EXPORTS; $(CPP) -P -DINCLUDE_VARIABLES -DG_OS_WIN32 -DALL_FILES - <$(srcdir)/gtk.symbols | sed -e '/^$$/d' -e 's/^/	/' -e 's/G_GNUC_[^ ]*//g') > $(srcdir)/gtk.def
++	(echo -e EXPORTS; $(CPP) -P -DINCLUDE_VARIABLES -DG_OS_WIN32 -DALL_FILES - <$(srcdir)/gtk.symbols | sed -e '/^$$/d' -e 's/^/	/' -e 's/G_GNUC_[^ ]*//g') > gtk.def
+ 
+ gtkalias.h: gtk.symbols
+ 	  $(PERL) $(srcdir)/makegtkalias.pl < $(srcdir)/gtk.symbols > gtkalias.h
+@@ -836,7 +836,7 @@ EXTRA_DIST += $(STOCK_ICONS)
+ #
+ # setup autogeneration dependencies
+ gen_sources = xgen-gdef xgen-gtbh xgen-gtic xgen-gmh xgen-gmc xgen-gmlh xgen-gmlc xgen-gtfsrc.c xgen-gtf
+-CLEANFILES = $(gen_sources)
++CLEANFILES = $(gen_sources) $(gtk_def)
+ 
+ BUILT_SOURCES = $(gtk_built_sources)
+ 
+@@ -1463,7 +1463,6 @@ EXTRA_DIST +=                   \
+ 	tree_minus.xbm          \
+ 	tree_minus.xpm		\
+ 	tree_plus.xpm		\
+-	gtk.def			\
+ 	gtk-builder-convert	\
+ 	gtk-win32.rc		\
+ 	gtk-win32.rc.in		\
+-- 
+GitLab
+