[vlc-devel] [PATCH 6/6] contrib: toolchain.cmake: enforce variables for android

[Alexandre Janniaux]

CMAKE_SYSTEM_PROCESSOR must match specific rules for Android, defined in
the CMake files: Modules/Platform/Android-Determine.cmake.  Instead, pass
down the ANDROID_ABI variable to the CMAKE_ANDROID_ARCH_ABI which will be
used to set the correct environment, including the processor variable.

Also enforce CMAKE_SYSTEM_NAME to have CMAKE_CROSSCOMPILE = true and
CMAKE_ANDROID_ARM_NEON with armeabi-v7a for correct neon support and
enable switch.
---
 contrib/src/main.mak | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/contrib/src/main.mak b/contrib/src/main.mak
index 4ce040bb4f..e0d8066ded 100644
--- a/contrib/src/main.mak
+++ b/contrib/src/main.mak
@@ -543,6 +543,9 @@ endif
 ifdef HAVE_DARWIN_OS
 CMAKE_SYSTEM_NAME = Darwin
 endif
+ifdef HAVE_ANDROID
+CMAKE_SYSTEM_NAME = Android
+endif
 
 ifdef HAVE_ANDROID
 CFLAGS += -DANDROID_NATIVE_API_LEVEL=$(ANDROID_API)
@@ -556,7 +559,30 @@ ifndef WITH_OPTIMIZATION
 else
 	echo "set(CMAKE_BUILD_TYPE Release)" >> $@
 endif
+
+ifdef HAVE_ANDROID
+# Android has special rules for detecting the architecture
+# and CMAKE_SYSTEM_PROCESSOR should match them.
+	echo "set(CMAKE_SYSTEM_VERSION ${ANDROID_API})" >> $@
+	echo "set(CMAKE_ANDROID_ARCH_ABI ${ANDROID_ABI})" >> $@
+
+# From CMake manual:
+# When Cross Compiling for Android and CMAKE_ANDROID_ARCH_ABI is set to
+# armeabi-v7a set CMAKE_ANDROID_ARM_NEON to ON to target ARM NEON devices.
+ifeq ($(ANDROID_ABI),armeabi-v7a)
+ifdef HAVE_NEON
+	echo "set(CMAKE_ANDROID_ARM_NEON ON)" >> $@
+else
+	echo "set(CMAKE_ANDROID_ARM_NEON OFF)" >> $@
+endif
+endif
+
+# Else use the default expected behaviour for other platforms
+else
 	echo "set(CMAKE_SYSTEM_PROCESSOR $(ARCH))" >> $@
+endif
+
+
 	if test -n "$(CMAKE_SYSTEM_NAME)"; then \
 		echo "set(CMAKE_SYSTEM_NAME $(CMAKE_SYSTEM_NAME))" >> $@; \
 	fi;
-- 
2.24.0