Unable to build Toybox with Android NDK

[eugenesan]

I followed instructions for building Toybox with Android NDK.
The newest version I was able to build with NDK (21-25 with API 29-33) was 0.8.7.
Strangely 0.8.5 wouldn't build while 0.8.4 and 0.8.3 did just fine.

Anyone had better luck?

This what I used to build it:

#!/bin/sh -x

#unzip android-ndk-r25c-linux-x86_64.zip
NDK_TC_DIR=~/Android/Sdk/ndk/25.2.9519653/toolchains/llvm/prebuilt/linux-x86_64/bin
NDK_TC=aarch64-linux-android-

cd ${NDK_TC_DIR}
test -f ${NDK_TC}cc || ln -s aarch64-linux-android33-clang ${NDK_TC}cc
test -f ${NDK_TC}strip || ln -s llvm-objcopy ${NDK_TC}strip
cd -

export PATH="${NDK_TC_DIR}:$PATH"

make distclean
make LDFLAGS=--static CROSS_COMPILE=${NDK_TC} defconfig toybox

Below is the failed build output of 0.8.9 (0.8.5+ fail with similar errors):

+ make distclean
cleaned
root cleaned
removed .config
+ make LDFLAGS=--static CROSS_COMPILE=aarch64-linux-android- defconfig toybox
cc -o kconfig/conf kconfig/conf.c kconfig/zconf.tab.c -DKBUILD_NO_NLS=1 \
	-DPROJECT_NAME=\"ToyBox\"
In file included from kconfig/zconf.tab.c:2340:
kconfig/confdata.c: In function ‘conf_write’:
kconfig/confdata.c:435:34: warning: ‘.tmpconfig.’ directive writing 11 bytes into a region of size between 1 and 128 [-Wformat-overflow=]
  435 |                 sprintf(tmpname, "%s.tmpconfig.%d", dirname, (int)getpid());
      |                                  ^~~~~~~~~~~~~~~~~
kconfig/confdata.c:435:17: note: ‘sprintf’ output between 13 and 150 bytes into a destination of size 128
  435 |                 sprintf(tmpname, "%s.tmpconfig.%d", dirname, (int)getpid());
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
scripts/genconfig.sh
kconfig/conf -D /dev/null Config.in > /dev/null
scripts/make.sh
Library probe
generated/{Config.in,newtoys.h,flags.h,globals.h,tags.h,help.h}
Compile toybox
..........................toys/lsb/passwd.c:71:45: error: implicit declaration of function 'getspnam' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
  if (*(pass = pw->pw_passwd)=='x' && (sp = getspnam(name))) pass = sp->sp_pwdp;
                                            ^
toys/lsb/passwd.c:71:43: warning: incompatible integer to pointer conversion assigning to 'struct spwd *' from 'int' [-Wint-conversion]
  if (*(pass = pw->pw_passwd)=='x' && (sp = getspnam(name))) pass = sp->sp_pwdp;
                                          ^ ~~~~~~~~~~~~~~
toys/lsb/passwd.c:71:71: error: incomplete definition of type 'struct spwd'
  if (*(pass = pw->pw_passwd)=='x' && (sp = getspnam(name))) pass = sp->sp_pwdp;
                                                                    ~~^
toys/lsb/passwd.c:58:10: note: forward declaration of 'struct spwd'
  struct spwd *sp;
         ^
toys/lsb/passwd.c:93:14: error: implicit declaration of function 'crypt' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
      pass = crypt(toybuf+2048, pw->pw_passwd);
             ^
toys/lsb/passwd.c:93:12: warning: incompatible integer to pointer conversion assigning to 'char *' from 'int' [-Wint-conversion]
      pass = crypt(toybuf+2048, pw->pw_passwd);
           ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
toys/lsb/passwd.c:103:17: error: implicit declaration of function 'crypt' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
    encrypted = crypt(toybuf, salt);
                ^
toys/lsb/passwd.c:103:15: warning: incompatible integer to pointer conversion assigning to 'char *' from 'int' [-Wint-conversion]
    encrypted = crypt(toybuf, salt);
              ^ ~~~~~~~~~~~~~~~~~~~
3 warnings and 4 errors generated.
.make: *** [Makefile:17: toybox] Error 1

[landley]

Not make defconfig, make android_defconfig. Some commands don't build under the NDK.

The biggest chunk of them is the shadow password stuff, which I have a patch locally to rewrite (fixes ~5 commands I think) but I've bumped that until next release...

[enh-google]

WAI and -- unlike macOS -- not obvious that make defconfig could ever auto-detect cross-compilation for Android...