Re: [Valgrind-users] Cross compilation issue for Android

[John R. <jr...@bi...>]

> Upon moving to next. It landed into another issue. seems it is not easy to cross compile the valgrind to Android as they mentioned https://valgrind.org/docs/manual/dist.readme-android.html <https://valgrind.org/docs/manual/dist.readme-android.html>
> 
> Should i need to contact valgrind developers list to support.
> 
> ../coregrind/link_tool_exe_linux 0x58000000 /local/mnt/workspace/Android_ndk/android-ndk-r23c/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android31-clang  -O3 --target=aarch64-linux-android31-clang 
> --gcc-toolchain=/local/mnt/workspace/Android_ndk/android-ndk-r23c/toolchains/llvm/prebuilt/linux-x86_64/bin/ --sysroot=/local/mnt/workspace/Android_ndk/android-ndk-r23c/toolchains/llvm/prebuilt/linux-x86_64/sysroot   -o memcheck-arm-linux  -m32 -O2 -g -Wall -Wmissing-prototypes -Wshadow 
> -Wpointer-arith -Wstrict-prototypes -Wmissing-declarations -Wcast-qual -Wwrite-strings -Wempty-body -Wformat -Wformat-security -Wignored-qualifiers -Wenum-conversion -finline-functions -fno-stack-protector -fno-strict-aliasing -fno-builtin -Wno-cast-align -Wno-self-assign -Wno-tautological-compare 
>   -marm -mcpu=cortex-a8 -O2 -static -nodefaultlibs -nostartfiles -u _start   -m32 -Wl,-z,noexecstack memcheck_arm_linux-mc_leakcheck.o memcheck_arm_linux-mc_malloc_wrappers.o memcheck_arm_linux-mc_main.o memcheck_arm_linux-mc_main_asm.o memcheck_arm_linux-mc_translate.o 
> memcheck_arm_linux-mc_machine.o memcheck_arm_linux-mc_errors.o ../coregrind/libcoregrind-arm-linux.a ../VEX/libvex-arm-linux.a
> ld: error: undefined symbol: __aeabi_uidivmod
>  >>> referenced by mc_leakcheck.c:837
>  >>>               memcheck_arm_linux-mc_leakcheck.o:(heuristic_reachedness)
>  >>> referenced by m_execontext.c:346
>  >>>               libcoregrind_arm_linux_a-m_execontext.o:(record_ExeContext_wrk2) in archive ../coregrind/libcoregrind-arm-linux.a
>  >>> referenced by m_execontext.c:346
>  >>>               libcoregrind_arm_linux_a-m_execontext.o:(record_ExeContext_wrk2) in archive ../coregrind/libcoregrind-arm-linux.a
>  >>> referenced 11 more times
>  >    [[snip]]

You should contact whoever supports aarch64-linux-android31-clang and complaln
that their linker step for static linking forgets to reference a static library
that contains __aeabi_uidivmod, __aeabi_d2ulz, __aeabi_ul2d, __aeabi_uldivmod,
__aeabi_uidiv, __aeabi_idiv, __aeabi_idivmod, and __aeabi_ldivmod .

I found them in:
-----
$ nm -gop --defined-only $(find . -name '*.a' 2>/dev/null)  | grep __aeabi_uidivmod
./Android/Sdk/build-tools/32.0.0/renderscript/lib/intermediates/armeabi-v7a/libcompiler_rt.a:aeabi_uidivmod.o:00000000 T __aeabi_uidivmod
./Android/Sdk/build-tools/32.1.0-rc1/renderscript/lib/intermediates/armeabi-v7a/libcompiler_rt.a:aeabi_uidivmod.o:00000000 T __aeabi_uidivmod
./Android/Sdk/build-tools/30.0.3/renderscript/lib/intermediates/armeabi-v7a/libcompiler_rt.a:aeabi_uidivmod.o:00000000 T __aeabi_uidivmod
$
-----
and similarly for the other undefined symbols.

Therefore a workaround is to append explicit names for the files that contain
those runtime symbols that you desire.

The hint on how to investigate this problem is in  valgrind/coregrind/link_tool_exe_linux
which is a well-documented perl script that contains
-----
# So: what we actually do:
#
#   pass the specified command to the linker as-is, except, ...

my $cmd = join(" ", @ARGV, "-static -Wl,-Ttext-segment=$ala");

#print "link_tool_exe_linux: $cmd\n";


# Execute the command:
my $r = system($cmd);
-----
which shows that aarch64-linux-android31-clang is at fault when static linking.
(Forgetting the case of static linking is a common error in cross-building systems.)