[OE-core] [PATCH] libepoxy: Fix build break for EGL_CAST dependency

[Tom Hochstein]

This is a backport [1] to fix the following build error:

| In file included from /home/r60874/upstream/xwayland/tmp/work/armv7at2hf-neon-mx6qdl-fslc-linux-gnueabi/gtk+3/3.22.17-r0/recipe-sysroot/usr/include/epoxy/egl.h:46:0,
|                  from ../../../gtk+-3.22.17/gdk/wayland/gdkglcontext-wayland.h:32,
|                  from ../../../gtk+-3.22.17/gdk/wayland/gdkglcontext-wayland.c:24:
| ../../../gtk+-3.22.17/gdk/wayland/gdkglcontext-wayland.c: In function 'gdk_wayland_gl_context_realize':
| ../../../gtk+-3.22.17/gdk/wayland/gdkglcontext-wayland.c:179:43: error: expected expression before 'EGLContext'
|                                          : EGL_NO_CONTEXT,
|                                            ^

[1] https://github.com/anholt/libepoxy/commit/ebe3a53db1c0bb34e1ca963b95d1f222115f93f8

Signed-off-by: Tom Hochstein <tom.hochstein at nxp.com>
---
 .../Add-fallback-definition-for-EGL-CAST.patch     | 31 ++++++++++++++++++++++
 meta/recipes-graphics/libepoxy/libepoxy_1.4.3.bb   |  3 ++-
 2 files changed, 33 insertions(+), 1 deletion(-)
 create mode 100644 meta/recipes-graphics/libepoxy/libepoxy/Add-fallback-definition-for-EGL-CAST.patch

diff --git a/meta/recipes-graphics/libepoxy/libepoxy/Add-fallback-definition-for-EGL-CAST.patch b/meta/recipes-graphics/libepoxy/libepoxy/Add-fallback-definition-for-EGL-CAST.patch
new file mode 100644
index 0000000..daa1785
--- /dev/null
+++ b/meta/recipes-graphics/libepoxy/libepoxy/Add-fallback-definition-for-EGL-CAST.patch
@@ -0,0 +1,31 @@
+Add fallback definition for EGL_CAST
+
+The EGL API update from d11104f introduced a dependency on the
+EGL_CAST() macro, provided by an updated eglplatform.h. Given that we
+don't provide eglplatform.h, add a fallback definition for if we're
+building against Mesa 17.0.x or similar.
+
+https://bugs.gentoo.org/show_bug.cgi?id=623926
+
+Upstream-Status: Backport [https://github.com/anholt/libepoxy/commit/ebe3a53db1c0bb34e1ca963b95d1f222115f93f8]
+
+Index: libepoxy-1.4.3/src/gen_dispatch.py
+===================================================================
+--- libepoxy-1.4.3.orig/src/gen_dispatch.py	2017-06-06 04:24:13.000000000 -0500
++++ libepoxy-1.4.3/src/gen_dispatch.py	2017-11-06 12:45:43.594966473 -0600
+@@ -491,6 +491,15 @@
+             self.outln('#include "epoxy/gl.h"')
+             if self.target == "egl":
+                 self.outln('#include "EGL/eglplatform.h"')
++                # Account for older eglplatform.h, which doesn't define
++                # the EGL_CAST macro.
++                self.outln('#ifndef EGL_CAST')
++                self.outln('#if defined(__cplusplus)')
++                self.outln('#define EGL_CAST(type, value) (static_cast<type>(value))')
++                self.outln('#else')
++                self.outln('#define EGL_CAST(type, value) ((type) (value))')
++                self.outln('#endif')
++                self.outln('#endif')
+         else:
+             # Add some ridiculous inttypes.h redefinitions that are
+             # from khrplatform.h and not included in the XML.  We
diff --git a/meta/recipes-graphics/libepoxy/libepoxy_1.4.3.bb b/meta/recipes-graphics/libepoxy/libepoxy_1.4.3.bb
index c8b398f..0172322 100644
--- a/meta/recipes-graphics/libepoxy/libepoxy_1.4.3.bb
+++ b/meta/recipes-graphics/libepoxy/libepoxy_1.4.3.bb
@@ -5,7 +5,8 @@ SECTION = "libs"
 LICENSE = "MIT"
 LIC_FILES_CHKSUM = "file://COPYING;md5=58ef4c80d401e07bd9ee8b6b58cf464b"
 
-SRC_URI = "https://github.com/anholt/${BPN}/releases/download/${PV}/${BP}.tar.xz"
+SRC_URI = "https://github.com/anholt/${BPN}/releases/download/${PV}/${BP}.tar.xz \
+           file://Add-fallback-definition-for-EGL-CAST.patch"
 SRC_URI[md5sum] = "af4c3ce0fb1143bdc4e43f85695a9bed"
 SRC_URI[sha256sum] = "0b808a06c9685a62fca34b680abb8bc7fb2fda074478e329b063c1f872b826f6"
 UPSTREAM_CHECK_URI = "https://github.com/anholt/libepoxy/releases"
-- 
1.9.1