Is the Output of Retdec Compilable?

[humanitiesclinic]

I can decompile binaries successfully. Can I check if I can then compile the output from the decompiler? Is the output C or just C-like?

[humanitiesclinic]

Ok I tried, with no success. Output:

Users-MacBook-Pro:retdec_output user$ gcc -o spray spray.c
spray.c:87:23: warning: implicit declaration of function '_getopt' is invalid in C99
      [-Wimplicit-function-declaration]
        int32_t v10 = _getopt((int32_t)a1, (char **)v6, (char *)v5); // 0x10000097c397416
                      ^
spray.c:104:35: warning: implicit declaration of function '_atoi' is invalid in C99
      [-Wimplicit-function-declaration]
                    int64_t v15 = _atoi((char *)*(int64_t *)v3); // 0x10000095d
                                  ^
spray.c:176:21: warning: implicit declaration of function '_clnt_create' is invalid in C99
      [-Wimplicit-function-declaration]
    int64_t * v25 = _clnt_create((char *)v24, 0x186ac, 1, "udp"); // 0x100000a06
                    ^
spray.c:176:15: warning: incompatible integer to pointer conversion initializing 'int64_t *'
      (aka 'long long *') with an expression of type 'int' [-Wint-conversion]
    int64_t * v25 = _clnt_create((char *)v24, 0x186ac, 1, "udp"); // 0x100000a06
              ^     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
spray.c:179:9: warning: implicit declaration of function '_clnt_pcreateerror' is invalid in
      C99 [-Wimplicit-function-declaration]
        _clnt_pcreateerror((char *)a2);
        ^
spray.c:181:16: warning: incompatible pointer to integer conversion returning 'int32_t *'
      (aka 'int *') from a function with result type 'int64_t' (aka 'long long')
      [-Wint-conversion]
        return &g7;
               ^~~
spray.c:187:9: warning: implicit declaration of function '_printf' is invalid in C99
      [-Wimplicit-function-declaration]
        _printf("sending %d packets of lnth %d to %s ...", a1, v27, (char *)v26);
        ^
spray.c:188:9: warning: implicit declaration of function '_fflush' is invalid in C99
      [-Wimplicit-function-declaration]
        _fflush((struct _IO_FILE *)*(int64_t *)*(int64_t *)0x100001018);
        ^
spray.c:198:21: warning: implicit declaration of function '_usleep' is invalid in C99
      [-Wimplicit-function-declaration]
                    _usleep(v9);
                    ^
spray.c:217:28: warning: implicit declaration of function '__asm_cvtsi2sd' is invalid in C99
      [-Wimplicit-function-declaration]
            int128_t v34 = __asm_cvtsi2sd((int64_t)v33); // 0x100000b3a
                           ^
spray.c:220:28: warning: implicit declaration of function '__asm_addsd' is invalid in C99
      [-Wimplicit-function-declaration]
            int128_t v37 = __asm_addsd(__asm_divsd(v36, g1), v34); // 0x100000b4c
                           ^
spray.c:220:40: warning: implicit declaration of function '__asm_divsd' is invalid in C99
      [-Wimplicit-function-declaration]
            int128_t v37 = __asm_addsd(__asm_divsd(v36, g1), v34); // 0x100000b4c
                                       ^
spray.c:221:27: warning: implicit declaration of function '__asm_movsd' is invalid in C99
      [-Wimplicit-function-declaration]
            int64_t v38 = __asm_movsd(v37); // 0x100000b59
                          ^
spray.c:227:17: warning: implicit declaration of function '__asm_xorps' is invalid in C99
      [-Wimplicit-function-declaration]
                __asm_xorps(v37, v37);
                ^
spray.c:228:32: warning: implicit declaration of function '__asm_cvtsi2sd_1' is invalid in
      C99 [-Wimplicit-function-declaration]
                int128_t v41 = __asm_cvtsi2sd_1(v40); // 0x100000b96
                               ^
spray.c:229:32: warning: implicit declaration of function '__asm_mulsd' is invalid in C99
      [-Wimplicit-function-declaration]
                int128_t v42 = __asm_mulsd(v41, g2); // 0x100000b9a
                               ^
spray.c:232:94: warning: implicit declaration of function '__asm_divsd_2' is invalid in C99
      [-Wimplicit-function-declaration]
  ..._printf("\t%d packets (%.2f%%) dropped\n", (int64_t)v40, (float64_t)(int64_t)__asm_d...
                                                                                  ^
spray.c:235:17: warning: implicit declaration of function '_puts' is invalid in C99
      [-Wimplicit-function-declaration]
                _puts("\tno packets dropped");
                ^
spray.c:241:18: warning: implicit declaration of function '__asm_movsd_3' is invalid in C99
      [-Wimplicit-function-declaration]
            g8 = __asm_movsd_3(v44);
                 ^
spray.c:251:5: warning: implicit declaration of function '_clnt_perror' is invalid in C99
      [-Wimplicit-function-declaration]
    _clnt_perror(v25, (char *)a2);
    ^
spray.c:262:5: warning: implicit declaration of function '__asm_movapd' is invalid in C99
      [-Wimplicit-function-declaration]
    __asm_movapd(v2);
    ^
spray.c:265:5: warning: implicit declaration of function '__asm_ucomisd' is invalid in C99
      [-Wimplicit-function-declaration]
    __asm_ucomisd(v5, g3);
    ^
spray.c:279:5: warning: implicit declaration of function '_fwrite' is invalid in C99
      [-Wimplicit-function-declaration]
    _fwrite((int64_t *)"usage: spray [-c count] [-l length] [-d delay] host\n", 52, ...
    ^
spray.c:288:9: warning: implicit declaration of function '_xdr_u_int' is invalid in C99
      [-Wimplicit-function-declaration]
    if (_xdr_u_int((int64_t *)a1, (int32_t *)a2) == 0) {
        ^
spray.c:315:12: warning: implicit declaration of function '_xdr_bytes' is invalid in C99
      [-Wimplicit-function-declaration]
    return _xdr_bytes((int64_t *)a1, (char **)(a2 + 8), (int32_t *)a2, 0x228d) != 0;
           ^
spray.c:327:12: warning: incompatible integer to pointer conversion returning 'int' from a
      function with result type 'int64_t *' (aka 'long long *') [-Wint-conversion]
    return _clnt_create(host, prog, vers, prot);
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
spray.c:399:12: warning: implicit declaration of function 'dyld_stub_binder' is invalid in
      C99 [-Wimplicit-function-declaration]
    return dyld_stub_binder();
           ^
27 warnings generated.
Undefined symbols for architecture x86_64:
  "___asm_addsd", referenced from:
      _entry_point in spray-4a3760.o
  "___asm_cvtsi2sd", referenced from:
      _entry_point in spray-4a3760.o
  "___asm_cvtsi2sd_1", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000c1e in spray-4a3760.o
  "___asm_divsd", referenced from:
      _entry_point in spray-4a3760.o
  "___asm_divsd_2", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000c1e in spray-4a3760.o
  "___asm_movapd", referenced from:
      _function_100000c1e in spray-4a3760.o
  "___asm_movsd", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000c1e in spray-4a3760.o
  "___asm_movsd_3", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000c1e in spray-4a3760.o
  "___asm_mulsd", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000c1e in spray-4a3760.o
  "___asm_ucomisd", referenced from:
      _function_100000c1e in spray-4a3760.o
  "___asm_xorps", referenced from:
      _entry_point in spray-4a3760.o
  "__atoi", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000d4e in spray-4a3760.o
  "__clnt_create", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000d54 in spray-4a3760.o
  "__clnt_pcreateerror", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000d5a in spray-4a3760.o
  "__clnt_perror", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000d60 in spray-4a3760.o
  "__fflush", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000d6c in spray-4a3760.o
  "__fwrite", referenced from:
      _function_100000c8f in spray-4a3760.o
      _function_100000d72 in spray-4a3760.o
  "__getopt", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000d78 in spray-4a3760.o
  "__printf", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000c1e in spray-4a3760.o
      _function_100000d7e in spray-4a3760.o
  "__puts", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000c1e in spray-4a3760.o
      _function_100000d84 in spray-4a3760.o
  "__usleep", referenced from:
      _entry_point in spray-4a3760.o
      _function_100000d8a in spray-4a3760.o
  "__xdr_bytes", referenced from:
      _function_100000d2b in spray-4a3760.o
      _function_100000d90 in spray-4a3760.o
  "__xdr_u_int", referenced from:
      _function_100000cbd in spray-4a3760.o
      _function_100000cf4 in spray-4a3760.o
      _function_100000d96 in spray-4a3760.o
  "_dyld_stub_binder", referenced from:
      _function_100000d9c in spray-4a3760.o
  "_main", referenced from:
     implicit entry/start for main executable
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

[s3rvac]

Hi. This question has already been answered in #529, so please refer to it and to the discussion in #45.

[UnrealKaraulov]

@s3rvac __asm_xorps is two unsigned 128bit operands, I got only 32bit signed in my output...

Missing data.

[greenozon]

@UnrealKaraulov not related to retdec, but might be interesting as well in your case - https://github.com/gaasedelen/microavx

[UnrealKaraulov]

@UnrealKaraulov not related to retdec, but might be interesting as well in your case - https://github.com/gaasedelen/microavx

but I use retdec and got this result, this is not retdec bug?

[greenozon]

seems yes..
do you have some sample binary to play with on this issue?

[UnrealKaraulov]

@greenozon yes but warning, binary contains RAT!

alt.zip
password infected

[UnrealKaraulov]

retdec processed xorps instructions as xorps 32bit,32bit instead of xorps 128bit,128bit

[greenozon]

yeah, seems IDA decompiles those AVX opcodes correctly, eg:
*v723 = _mm_xor_ps(*v723, v778);
etc..
so it operates on vars, not absolute numbers

[greenozon]

in my understanding the thing is that retdec does not have any translations for these kind of CPU opcodes, so it applies default behavior
eg:

retdec/src/capstone2llvmir/x86/x86_init.cpp

Line 819 in 04df6de

{X86_INS_MOVAPS, nullptr},