[[ Bug 19931 ]] Statically link libstdc++ in Android shared libs

livecodeali · livecodeali · commit e0c67cf7115d · 2017-07-07T17:05:00.000+01:00
Since we statically link libstdc++ in the main Android executable
now, symbols in libstdc++ not used by it get stripped. So, dlopen
fails on shared libraries that use any symbols in libstdc++ which
are not used by (and therefore are stripped from) the main executable.

This patch ensures that shared libraries statically link libstdc++
themselves so that they have the required symbols.

Additionally, the sqlite driver needs the math library, so statically
link to libm.
diff --git a/config/android-settings.gypi b/config/android-settings.gypi
@@ -2,6 +2,7 @@
 	'variables':
 	{
 		'c++_std': '<!(echo ${CXX_STD:-c++11})',
+		'android_lib_path%': '<!(echo ${ANDROID_LIB_PATH})',
 	},
 
 	'cflags':
@@ -30,6 +31,17 @@
 	
 	'target_conditions':
 	[
+		[
+			'_type == "loadable_module"',
+			{
+				'ldflags':
+				[
+					'-L<(android_lib_path)',
+					'-lstdc++',
+				],
+
+			},
+		],
 		[
 			'silence_warnings == 0',
 			{
diff --git a/docs/development/build-android.md b/docs/development/build-android.md
@@ -89,10 +89,12 @@ ANDROID_PLATFORM=android-17
 ANDROID_NDK=${TOOLCHAIN}/android-ndk-r14
 ANDROID_SDK=${TOOLCHAIN}/android-sdk-linux
 ANDROID_BUILD_TOOLS=25.0.2
+ANDROID_LIB_PATH=${TOOLCHAIN}/standalone/${TRIPLE}/lib
 
 export JAVA_SDK
 export CC CXX LINK AR
 export ANDROID_PLATFORM ANDROID_NDK ANDROID_SDK ANDROID_BUILD_TOOLS
+export ANDROID_LIB_PATH
 ````
 
 ### Generating makefiles
diff --git a/docs/notes/bugfix-19931.md b/docs/notes/bugfix-19931.md
@@ -0,0 +1 @@
+# Fix loading of shared libraries on Android
diff --git a/revdb/revdb.gyp b/revdb/revdb.gyp
@@ -488,6 +488,10 @@
 							# Error in ../../thirdparty/libsqlite/include/qry_dat.h
 							'-Werror=return-type',
 						],
+						'libraries':
+						[
+							'-lm',
+						],
 					},
 				],
 				[

Original file line number	Diff line number	Diff line change
`@@ -2,6 +2,7 @@`
`2`	`2`	`'variables':`
`3`	`3`	`{`
`4`	`4`	`'c++_std': '<!(echo ${CXX_STD:-c++11})',`
	`5`	`+ 'android_lib_path%': '<!(echo ${ANDROID_LIB_PATH})',`
`5`	`6`	`},`
`6`	`7`
`7`	`8`	`'cflags':`
`@@ -30,6 +31,17 @@`
`30`	`31`
`31`	`32`	`'target_conditions':`
`32`	`33`	`[`
	`34`	`+ [`
	`35`	`+ '_type == "loadable_module"',`
	`36`	`+ {`
	`37`	`+ 'ldflags':`
	`38`	`+ [`
	`39`	`+ '-L<(android_lib_path)',`
	`40`	`+ '-lstdc++',`
	`41`	`+ ],`
	`42`	`+`
	`43`	`+ },`
	`44`	`+ ],`
`33`	`45`	`[`
`34`	`46`	`'silence_warnings == 0',`
`35`	`47`	`{`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	`+# Fix loading of shared libraries on Android`