LLVM找不到Clang二进制文件

Question

我刚刚使用编译器-rt构建并安装了LLVM Clang 3.5.0。 clang二进制文件似乎可以工作，但是无法构建简单的测试程序：

$ cat hello.c 
#include <stdio.h>
int main(int argc, char **argv) {
    printf("Hello World\n");
    return 0;
}

构建它失败， error: unable to execute command: Executable "" doesn't exist!

$ clang hello.c -o hello
error: unable to execute command: Executable "" doesn't exist!

可执行的“”？ 有趣...

对其进行进一步的调试显示，clang尝试调用自身以构建.o目标文件，然后通过ld链接该文件，但不知道其明显存在的位置。

$ clang -### hello.c -o hello
clang version 3.5.0 (tags/RELEASE_350/final)
Target: x86_64-alpine-linux-musl
Thread model: posix
 "" "-cc1" "-triple" "x86_64-alpine-linux-musl" "-emit-obj" "-mrelax-all" "-disable-free" "-main-file-name" "hello.c" "-mrelocation-model" "static" "-mdisable-fp-elim" "-fmath-errno" "-masm-verbose" "-mconstructor-aliases" "-munwind-tables" "-fuse-init-array" "-target-cpu" "x86-64" "-target-linker-version" "2.24" "-dwarf-column-info" "-resource-dir" "../lib/clang/3.5.0" "-internal-isystem" "/usr/local/include" "-internal-isystem" "../lib/clang/3.5.0/include" "-internal-externc-isystem" "/include" "-internal-externc-isystem" "/usr/include" "-fdebug-compilation-dir" "/" "-ferror-limit" "19" "-fmessage-length" "158" "-mstackrealign" "-fobjc-runtime=gcc" "-fdiagnostics-show-option" "-o" "/tmp/hello-37746e.o" "-x" "c" "hello.c"
 "/usr/bin/ld" "-z" "relro" "--eh-frame-hdr" "-m" "elf_x86_64" "-dynamic-linker" "/lib/ld-musl-x86_64.so.1" "-o" "hello" "/usr/bin/../lib/gcc/x86_64-alpine-linux-musl/4.8.3/../../../crt1.o" "/usr/bin/../lib/gcc/x86_64-alpine-linux-musl/4.8.3/../../../crti.o" "/usr/bin/../lib/gcc/x86_64-alpine-linux-musl/4.8.3/crtbegin.o" "-L/usr/bin/../lib/gcc/x86_64-alpine-linux-musl/4.8.3" "-L/usr/bin/../lib/gcc/x86_64-alpine-linux-musl/4.8.3/../../../../x86_64-alpine-linux-musl/lib" "-L/usr/bin/../lib/gcc/x86_64-alpine-linux-musl/4.8.3/../../.." "-L/../lib" "-L/lib" "-L/usr/lib" "/tmp/hello-37746e.o" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "/usr/bin/../lib/gcc/x86_64-alpine-linux-musl/4.8.3/crtend.o" "/usr/bin/../lib/gcc/x86_64-alpine-linux-musl/4.8.3/../../../crtn.o"

当我运行第一行将/usr/bin/clang放在第一行时，它的构建就很好了：

$ /usr/bin/clang "-cc1" "-triple" "x86_64-alpine-linux-musl" "-emit-obj" "-mrelax-all" "-disable-free" "-main-file-name" "hello.c" "-mrelocation-model" "static" "-mdisable-fp-elim" "-fmath-errno" "-masm-verbose" "-mconstructor-aliases" "-munwind-tables" "-target-cpu" "x86-64" "-target-linker-version" "2.24" "-dwarf-column-info" "-resource-dir" "../lib/clang/3.5.0" "-internal-isystem" "/usr/local/include" "-internal-isystem" "../lib/clang/3.5.0/include" "-internal-externc-isystem" "/include" "-internal-externc-isystem" "/usr/include" "-fdebug-compilation-dir" "/" "-ferror-limit" "19" "-fmessage-length" "158" "-mstackrealign" "-fobjc-runtime=gcc" "-fdiagnostics-show-option" "-o" "/tmp/hello-4f64bb.o" "-x" "c" "hello.c"
$ 

然后/usr/bin/ld就能很好地链接它，导致：

$ ./hello
Hello World

Anny建议我在配置/构建过程中拧了些什么？

Answer 1

lang声源分析表明，Linux上的“ c声”程序使用/proc/self/exe来查找其二进制文件的真实路径。 我在没有/ proc挂载的chroot中运行，因此失败了。

mount -t proc proc /proc

解决问题