tl;dr
如何将 Ada 源代码编译为静态库文件，适用于运行 iOS 的 iPad 目标上的应用程序进行链接？ (GCC 不是必需的。也欢迎使用 LLVM 或其他解决方案!)

我有一个大型的可移植 Ada 代码库，我想在 iPad/iOS 项目中使用这些代码。我的主机操作系统是 Mac OS X 10.9(运行安装在 /opt/local 和 MacPorts 的 GCC 4.8.1)。为此，我正在尝试构建一个支持 Ada 的 GCC ARM 交叉编译器。

我能够构建一个可以创建 ARM 可执行文件的工作 GCC 和 GNAT，但我似乎无法构建或安装 Ada 标准库，这是构建我的 Ada 代码所必需的

我使用的源码包:

gcc-4.8.1
binutils-2.24
libiconv-1.14
gmp-5.1.3
mpc-1.0.2
mpfr-3.1.2

GCC 构建配置:

$ bin/arm-none-eabi-gcc -v --version
Using built-in specs.
COLLECT_GCC=bin/arm-none-eabi-gcc
COLLECT_LTO_WRAPPER=/Users/ardnew/cross/libexec/gcc/arm-none-eabi/4.8.1/lto-wrapper
arm-none-eabi-gcc (GCC) 4.8.1
Copyright (C) 2013 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.


Target: arm-none-eabi
Configured with: /Users/ardnew/cross/src/gcc-4.8.1/configure --target=arm-none-eabi --prefix=/Users/ardnew/cross --with-cpu=cortex-a8 --enable-languages=c,ada --disable-multilib --enable-interwork --disable-threads --disable-shared --disable-nls --disable-lto --disable-libssp --disable-decimal-float --disable-libgomp --disable-libmudflap
Thread model: single
gcc version 4.8.1 (GCC)
COLLECT_GCC_OPTIONS='-v' '--version' '-mcpu=cortex-a8'
 /Users/ardnew/cross/libexec/gcc/arm-none-eabi/4.8.1/cc1 -quiet -v -D__USES_INITFINI__ help-dummy -quiet -dumpbase help-dummy -mcpu=cortex-a8 -auxbase help-dummy -version --version -o /var/folders/4c/y_sll7bj6b9bt15389wr66_80000gn/T//ccrSSKFx.s
GNU C (GCC) version 4.8.1 (arm-none-eabi)
  compiled by GNU C version 4.8.1, GMP version 5.1.3, MPFR version 3.1.2, MPC version 1.0.2
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
COLLECT_GCC_OPTIONS='-v' '--version' '-mcpu=cortex-a8'
 /Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/bin/as -mcpu=cortex-a8 -meabi=5 --version -o /var/folders/4c/y_sll7bj6b9bt15389wr66_80000gn/T//ccZYvQLp.o /var/folders/4c/y_sll7bj6b9bt15389wr66_80000gn/T//ccrSSKFx.s
GNU assembler (GNU Binutils) 2.24
Copyright 2013 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or later.
This program has absolutely no warranty.
This assembler was configured for a target of `arm-none-eabi'.
COMPILER_PATH=/Users/ardnew/cross/libexec/gcc/arm-none-eabi/4.8.1/:/Users/ardnew/cross/libexec/gcc/arm-none-eabi/4.8.1/:/Users/ardnew/cross/libexec/gcc/arm-none-eabi/:/Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/:/Users/ardnew/cross/lib/gcc/arm-none-eabi/:/Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/bin/
LIBRARY_PATH=/Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/:/Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/lib/
COLLECT_GCC_OPTIONS='-v' '--version' '-mcpu=cortex-a8'
 /Users/ardnew/cross/libexec/gcc/arm-none-eabi/4.8.1/collect2 -X --version /Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/crti.o /Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/crtbegin.o crt0.o -L/Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1 -L/Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/lib /var/folders/4c/y_sll7bj6b9bt15389wr66_80000gn/T//ccZYvQLp.o --start-group -lgcc -lc --end-group /Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/crtend.o /Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/crtn.o
collect2 version 4.8.1
/Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/bin/ld -X --version /Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/crti.o /Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/crtbegin.o crt0.o -L/Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1 -L/Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/lib /var/folders/4c/y_sll7bj6b9bt15389wr66_80000gn/T//ccZYvQLp.o --start-group -lgcc -lc --end-group /Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/crtend.o /Users/ardnew/cross/lib/gcc/arm-none-eabi/4.8.1/crtn.o
GNU ld (GNU Binutils) 2.24
Copyright 2013 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or (at your option) a later version.
This program has absolutely no warranty.

测试程序以确保其构建 ARM 二进制文件:

$ cat told_unit1.adb told_unit1.ads

--
-- FILE: told_unit1.adb
--
with Ada.Text_IO;
use Ada.Text_IO;

package body told_unit1 is

  procedure hello is
  begin
    put_line("hello, world");
  end hello;

  function double(x : in float) return float is
  begin
    return x + x;
  end double;

end told_unit1;


--
-- FILE: told_unit1.ads
--
package told_unit1 is

  procedure hello;
  pragma Export
  (
    convention     =>  C,
    entity         =>  hello,
    external_name  =>  "ada_hello"
  );

  function double(x : in float) return float;
  pragma Export
  (
    convention     =>  C,
    entity         =>  double,
    external_name  =>  "ada_double"
  );

end told_unit1;

然后编译 Ada 代码并使用 file 检查它:

$ arm-none-eabi-gcc -c told_unit1.adb

$ file told_unit1.o
told_unit1.o: ELF 32-bit LSB relocatable, ARM, version 1 (SYSV), not stripped

然后当我尝试绑定(bind)库对象文件时，它吐了:

$ arm-none-eabi-gnatbind -aO$ADA_OBJECT_PATH -Ltold told_unit1
error: "a-textio.ali" not found, "a-textio.adb" must be compiled

回到我的 GCC 构建日志，我发现 libada(我认为它是 GNAT 的一部分)从未构建过。当我尝试从 GCC 构建目录运行 make all-target-libada 时，它最终告诉我:

Configuring in arm-none-eabi/libada
configure: loading cache ./config.cache
checking build system type... x86_64-apple-darwin13.1.0
checking host system type... arm-none-eabi
checking target system type... arm-none-eabi
checking for arm-none-eabi-gcc...  /Users/ardnew/cross/src/gcc-4.8.1-obj/./gcc/xgcc -B/Users/ardnew/cross/src/gcc-4.8.1-obj/./gcc/ -B/Users/ardnew/cross/arm-none-eabi/bin/ -B/Users/ardnew/cross/arm-none-eabi/lib/ -isystem /Users/ardnew/cross/arm-none-eabi/include -isystem /Users/ardnew/cross/arm-none-eabi/sys-include
checking for C compiler default output file name...
configure: error: in `/Users/ardnew/cross/src/gcc-4.8.1-obj/arm-none-eabi/libada':
configure: error: C compiler cannot create executables
See `config.log' for more details.
make: *** [configure-target-libada] Error 1

所以我去检查它引用的 config.log 并找到以下内容:

configure:2351: $? = 0
configure:2340:  /Users/ardnew/cross/src/gcc-4.8.1-obj/./gcc/xgcc -B/Users/ardnew/cross/src/gcc-4.8.1-obj/./gcc/ -B/Users/ardnew/cross/arm-none-eabi/bin/ -B/Users/ardnew/cross/arm-none-eabi/lib/ -isystem /Users/ardnew/cross/arm-none-eabi/include -isystem /Users/ardnew/cross/arm-none-eabi/sys-include    -v >&5
COLLECT_LTO_WRAPPER=/Users/ardnew/cross/src/gcc-4.8.1-obj/./gcc/lto-wrapper
Target: arm-none-eabi
Configured with: /Users/ardnew/cross/src/gcc-4.8.1/configure --target=arm-none-eabi --prefix=/Users/ardnew/cross --with-cpu=cortex-a8 --enable-languages=c,ada --disable-multilib --enable-interwork --disable-threads --disable-shared --disable-nls --disable-lto --disable-libssp --disable-decimal-float --disable-libgomp --disable-libmudflap
configure:2351: $? = 0
xgcc: error: unrecognized command line option '-qversion'
xgcc: fatal error: no input files
compilation terminated.
configure:2351: $? = 1
configure:2371: checking for C compiler default output file name
configure:2393:  /Users/ardnew/cross/src/gcc-4.8.1-obj/./gcc/xgcc -B/Users/ardnew/cross/src/gcc-4.8.1-obj/./gcc/ -B/Users/ardnew/cross/arm-none-eabi/bin/ -B/Users/ardnew/cross/arm-none-eabi/lib/ -isystem /Users/ardnew/cross/arm-none-eabi/include -isystem /Users/ardnew/cross/arm-none-eabi/sys-include    -g -O2   conftest.c  >&5
/Users/ardnew/cross/arm-none-eabi/bin/ld: cannot find crt0.o: No such file or directory
/Users/ardnew/cross/arm-none-eabi/bin/ld: cannot find -lg
/Users/ardnew/cross/arm-none-eabi/bin/ld: cannot find -lc
collect2: error: ld returned 1 exit status
configure:2397: $? = 1
configure:2434: result:
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_NAME ""
| #define PACKAGE_TARNAME ""
| #define PACKAGE_VERSION ""
| #define PACKAGE_STRING ""
| #define PACKAGE_BUGREPORT ""
| #define PACKAGE_URL ""
| /* end confdefs.h.  */
|
| int
| main ()
| {
|
|   ;
|   return 0;
| }
configure:2440: error: in `/Users/ardnew/cross/src/gcc-4.8.1-obj/arm-none-eabi/libada':
configure:2444: error: C compiler cannot create executables
See `config.log' for more details.

所以在这一点上，我完全不知所措，不确定下一步该怎么做。看起来我可能缺少 ARM 的 C 运行时库？

任何为 ARM 目标配置 GNAT/libada 的帮助都会很棒。

或者，是否有更简单的方法从 Xcode iOS 项目链接 Ada 库？

最佳答案

不幸的是，答案是没有自动魔术工具可以完成此任务。您可以在事后使用工具来验证翻译，但您想要的还不可用。

我过去不得不处理同样的问题。一个不同的答案也会极大地改变我的一个项目的预算。也许有一天。

虽然我承认，但我认为最终存在足够多的不兼容性，以至于您需要彻底改变您的源代码——降低您希望在此处实现的目标的值(value)。最后，新的投资是一个无赖，但如果你负担得起的话，会带来更好的来源。

关于ios - 适用于 iOS 目标的 Ada 交叉编译器，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/23397596/