Many people seem to be unaware that decompilers have a decompilation export feature, which is particularly beneficial when you are trying to parse or recompile decompiled code.

Ghidra

Here is a random function from /bin/ls that I decompiled using Ghidra, and simply copied the output from the decompilation window:

void FUN_0010b1b0(undefined8 *param_1,undefined8 *param_2)

{
  char *__s;
  char *__s_00;
  int iVar1;
  char *__s1;
  char *__s2;
  int *piVar2;
  
  __s = (char *)*param_2;
  __s1 = strrchr(__s,0x2e);
  __s_00 = (char *)*param_1;
  __s2 = strrchr(__s_00,0x2e);
  if (__s2 == (char *)0x0) {
    __s2 = "";
  }
  if (__s1 == (char *)0x0) {
    __s1 = "";
  }
  piVar2 = __errno_location();
  *piVar2 = 0;
  iVar1 = strcoll(__s1,__s2);
  if (iVar1 == 0) {
    strcoll(__s,__s_00);
    return;
  }
  return;
}

This code does not compile.

gcc -c a.c
a.c:1:19: error: unknown type name ‘undefined8’
    1 | void FUN_0010b1b0(undefined8 *param_1,undefined8 *param_2)
      |                   ^~~~~~~~~~
a.c:1:39: error: unknown type name ‘undefined8’
    1 | void FUN_0010b1b0(undefined8 *param_1,undefined8 *param_2)
      |                                       ^~~~~~~~~~

However, we can use Ghidra's decompiler exporter to decompile the function AND emit a header file that will define the types and declare the functions used in the decompiled code. Unfortunately, this is a little bit awkward to do for one function. I suggest the following process:

In the CodeBrowser, select the function you want to decompile in the Listing (disassembly) window.
In the CodeBrowser, navigate to File → Export Program.
Select "C/C++" as the Format.
Ensure that the "Selection Only" checkbox is checked.
In the Options dialog, check both the "Create Header File (.h)" and "Create C File (.c)" options.
Click OK.

This will create a decompiled source file ls.c containing type definitions for types used in the decompiled code, such as undefined8.

And if you try to compile the generated ls.c file, it will compile successfully:

gcc -c ls.c
ls.c: In function ‘FUN_0010b1b0’:
ls.c:630:10: warning: implicit declaration of function ‘strrchr’ [-Wimplicit-function-declaration]
  630 |   __s1 = strrchr(__s,0x2e);
      |          ^~~~~~~
ls.c:1:1: note: include ‘<string.h>’ or provide a declaration of ‘strrchr’
  +++ |+#include <string.h>
    1 | typedef unsigned char   undefined;
ls.c:630:10: warning: incompatible implicit declaration of built-in function ‘strrchr’ [-Wbuiltin-declaration-mismatch]
  630 |   __s1 = strrchr(__s,0x2e);
      |          ^~~~~~~
ls.c:630:10: note: include ‘<string.h>’ or provide a declaration of ‘strrchr’
ls.c:639:12: warning: implicit declaration of function ‘__errno_location’ [-Wimplicit-function-declaration]
  639 |   piVar2 = __errno_location();
      |            ^~~~~~~~~~~~~~~~
ls.c:639:10: warning: assignment to ‘int *’ from ‘int’ makes pointer from integer without a cast [-Wint-conversion]
  639 |   piVar2 = __errno_location();
      |          ^
ls.c:641:11: warning: implicit declaration of function ‘strcoll’ [-Wimplicit-function-declaration]
  641 |   iVar1 = strcoll(__s1,__s2);
      |           ^~~~~~~

Hurray!

This is slightly oversimplified. You can see the compiler's warnings that we did not have declarations for strrchr, __errno_location, and strcoll. Ghidra can generate these declarations, but didn't because we used the "Selection Only" option. To get these declarations, you can use an approach like the following:

Use "Export Program" to export the entire program. Under the "Options" dialog, check only the "Create Header File (.h)" option.
Use "Export Program" to export only the function you care about, but this time check only the "Create C File (.c)" option.
Remove type definitions from the generated C file, and instead include the generated header file.
Cross your fingers.

Unfortunately, this header file does not always compile. Here are some errors that I obtained when trying to compile the header for /bin/ls:

In file included from FUN_0010b1b0.c:1:
FUN_0010b1b0.h:671:6: warning: conflicting types for built-in function ‘__snprintf_chk’; expected ‘int(char *, long unsigned int,  int,  long unsigned int,  const char *, ...)’ [-Wbuiltin-declaration-mismatch]
  671 | void __snprintf_chk(void);
      |      ^~~~~~~~~~~~~~
FUN_0010b1b0.h:682:5: error: ‘sigaction’ redeclared as different kind of symbol
  682 | int sigaction(int __sig,sigaction *__act,sigaction *__oact);
      |     ^~~~~~~~~
FUN_0010b1b0.h:294:26: note: previous declaration of ‘sigaction’ with type ‘sigaction’
  294 | typedef struct sigaction sigaction, *Psigaction;
      |                          ^~~~~~~~~
FUN_0010b1b0.h:695:6: warning: conflicting types for built-in function ‘dcgettext’; expected ‘char *(const char *, const char *, int)’ [-Wbuiltin-declaration-mismatch]
  695 | void dcgettext(void);
      |      ^~~~~~~~~
[truncated]

This is probably because Ghidra's type manager includes multiple definitions for some types, such as sigaction. I have opened a Ghidra issue for these problems. Hopefully the Ghidra developers will commit to fixing these problems in the header file, since it would significantly improve the usability of the decompiler output.

Here is a ghidra-scala-loader script that can do the above steps for you from the command line.

Hex-Rays

IDA/Hex-Rays has a similar feature, but it is much more straightforward. Simply select File → Create C File, and it will generate a C file that includes all the necessary type definitions and function declarations. It does include defs.h, which is a file that contains type definitions for Hex-Rays. You can find that in the Hex-Rays SDK or elsewhere.

I'm trying to document a few things that I do infrequently enough that I tend to forget how to do them, and need to rediscover the process each time. Next in this series is debugging the Ghidra decompiler. This is one of the only resources I know of that discusses this!

The process is roughly:

cd /path/to/ghidra/Ghidra/Features/Decompiler/src/decompile/cpp
make decomp_dbg
Inside of Ghidra, right click on the "Debug Function Decompilation" menu item and save the XML file somewhere.
Run SLEIGHHOME=/path/to/ghidra ./decomp_dbg. You should now be in the decomp_dbg interpreter.
Use restore /path/to/debug.xml
Use load function target_func
Optionally use trace address insn_address
Finally run decompile

Here's a full example:

~/g/g/G/F/D/s/d/cpp $ env SLEIGHHOME=/home/ed/ghidra/ghidra_10.4_PUBLIC/ ./decomp_dbg
[decomp]> restore /tmp/mydebug.xml
/tmp/mydebug.xml successfully loaded: Intel/AMD 32-bit x86
[decomp]> load function main
Function main: 0x00411530
[decomp]> trace address 0x4115ec
OK (1 ranges)
[decomp]> decompile
Decompiling main
DEBUG 0: extrapopsetup
0x004115ec:200: **
   0x004115ec:200: ESP(0x004115ec:200) = ESP(free) + #0x4

DEBUG 1: funclink
0x004115ec:a5: call fCls3:8(free)
   0x004115ec:a5: EAX(0x004115ec:a5) = call fCls3:8(free)(ECX(free),u0x10000019:1(0x004115ec:212))
0x004115ec:211: **
   0x004115ec:211: u0x10000015(0x004115ec:211) = ESP(free) + #0x0
0x004115ec:212: **
   0x004115ec:212: u0x10000019:1(0x004115ec:212) = *(ram,u0x10000015(0x004115ec:211))

DEBUG 2: heritage
0x004115ec:248: **
   0x004115ec:248: ECX(0x004115ec:248) = [create] i0x004115ec:a5:8(free)
0x004115ec:25a: **
   0x004115ec:25a: EDX(0x004115ec:25a) = [create] i0x004115ec:a5:8(free)
0x004115ec:26f: **
   0x004115ec:26f: CF(0x004115ec:26f) = CF(0x004115dd:96) [] i0x004115ec:a5:8(free)
0x004115ec:280: **
   0x004115ec:280: PF(0x004115ec:280) = PF(0x004115dd:9e) [] i0x004115ec:a5:8(free)
0x004115ec:291: **
   0x004115ec:291: ZF(0x004115ec:291) = ZF(0x004115dd:9a) [] i0x004115ec:a5:8(free)
0x004115ec:2a2: **
   0x004115ec:2a2: SF(0x004115ec:2a2) = SF(0x004115dd:99) [] i0x004115ec:a5:8(free)
0x004115ec:2b3: **
   0x004115ec:2b3: OF(0x004115ec:2b3) = OF(0x004115dd:97) [] i0x004115ec:a5:8(free)
0x004115ec:2c4: **
   0x004115ec:2c4: EIP(0x004115ec:2c4) = EIP(0x004115c8:2c3) [] i0x004115ec:a5:8(free)
0x004115ec:a3: ESP(0x004115ec:a3) = ESP(free) - #0x4
   0x004115ec:a3: ESP(0x004115ec:a3) = ESP(0x004115cd:86) - #0x4
0x004115ec:a4: *(ram,ESP(free)) = #0x4115f1
   0x004115ec:a4: *(ram,ESP(0x004115ec:a3)) = #0x4115f1
0x004115ec:211: u0x10000015(0x004115ec:211) = ESP(free) + #0x0
   0x004115ec:211: u0x10000015(0x004115ec:211) = ESP(0x004115ec:a3) + #0x0
0x004115ec:a5: EAX(0x004115ec:a5) = call fCls3:8(free)(ECX(free),u0x10000019:1(0x004115ec:212))
   0x004115ec:a5: EAX(0x004115ec:a5) = call fCls3:8(free)(ECX(0x004115e6:a2),u0x10000019:1(0x004115ec:212))
0x004115ec:200: ESP(0x004115ec:200) = ESP(free) + #0x4
   0x004115ec:200: ESP(0x004115ec:200) = ESP(0x004115ec:a3) + #0x4

DEBUG 3: deadcode
0x004115ec:248: ECX(0x004115ec:248) = [create] i0x004115ec:a5:8(free)
   0x004115ec:248: **
0x004115ec:25a: EDX(0x004115ec:25a) = [create] i0x004115ec:a5:8(free)
   0x004115ec:25a: **
0x004115ec:26f: CF(0x004115ec:26f) = CF(0x004115dd:96) [] i0x004115ec:a5:8(free)
   0x004115ec:26f: **
0x004115ec:280: PF(0x004115ec:280) = PF(0x004115dd:9e) [] i0x004115ec:a5:8(free)
   0x004115ec:280: **
0x004115ec:291: ZF(0x004115ec:291) = ZF(0x004115dd:9a) [] i0x004115ec:a5:8(free)
   0x004115ec:291: **
0x004115ec:2a2: SF(0x004115ec:2a2) = SF(0x004115dd:99) [] i0x004115ec:a5:8(free)
   0x004115ec:2a2: **
0x004115ec:2b3: OF(0x004115ec:2b3) = OF(0x004115dd:97) [] i0x004115ec:a5:8(free)
   0x004115ec:2b3: **
0x004115ec:2c4: EIP(0x004115ec:2c4) = EIP(0x004115c8:2c3) [] i0x004115ec:a5:8(free)
   0x004115ec:2c4: **

DEBUG 4: sub2add
0x004115ec:2e4: **
   0x004115ec:2e4: u0x100000a0(0x004115ec:2e4) = #0x4 * #0xffffffff
0x004115ec:a3: ESP(0x004115ec:a3) = ESP(0x004115cd:86) - #0x4
   0x004115ec:a3: ESP(0x004115ec:a3) = ESP(0x004115cd:86) + u0x100000a0(0x004115ec:2e4)

DEBUG 5: propagatecopy
0x004115ec:a5: EAX(0x004115ec:a5) = call fCls3:8(free)(ECX(0x004115e6:a2),u0x10000019:1(0x004115ec:212))
   0x004115ec:a5: EAX(0x004115ec:a5) = call fCls3:8(free)(u0x00007a80(0x004115e6:a1),u0x10000019:1(0x004115ec:212))

DEBUG 6: identityel
0x004115ec:211: u0x10000015(0x004115ec:211) = ESP(0x004115ec:a3) + #0x0
   0x004115ec:211: u0x10000015(0x004115ec:211) = ESP(0x004115ec:a3)

DEBUG 7: propagatecopy
0x004115ec:212: u0x10000019:1(0x004115ec:212) = *(ram,u0x10000015(0x004115ec:211))
   0x004115ec:212: u0x10000019:1(0x004115ec:212) = *(ram,ESP(0x004115ec:a3))

DEBUG 8: collapseconstants
0x004115ec:2e4: u0x100000a0(0x004115ec:2e4) = #0x4 * #0xffffffff
   0x004115ec:2e4: u0x100000a0(0x004115ec:2e4) = #0xfffffffc

DEBUG 9: propagatecopy
0x004115ec:a3: ESP(0x004115ec:a3) = ESP(0x004115cd:86) + u0x100000a0(0x004115ec:2e4)
   0x004115ec:a3: ESP(0x004115ec:a3) = ESP(0x004115cd:86) + #0xfffffffc

DEBUG 10: addmultcollapse
0x004115ec:200: ESP(0x004115ec:200) = ESP(0x004115ec:a3) + #0x4
   0x004115ec:200: ESP(0x004115ec:200) = ESP(0x004115cd:86) + #0x0

DEBUG 11: earlyremoval
0x004115ec:211: u0x10000015(0x004115ec:211) = ESP(0x004115ec:a3)
   0x004115ec:211: **

DEBUG 12: earlyremoval
0x004115ec:2e4: u0x100000a0(0x004115ec:2e4) = #0xfffffffc
   0x004115ec:2e4: **

DEBUG 13: addmultcollapse
0x004115ec:a3: ESP(0x004115ec:a3) = ESP(0x004115cd:86) + #0xfffffffc
   0x004115ec:a3: ESP(0x004115ec:a3) = ESP(0x004115aa:26a) + #0xfffffffc

DEBUG 14: identityel
0x004115ec:200: ESP(0x004115ec:200) = ESP(0x004115cd:86) + #0x0
   0x004115ec:200: ESP(0x004115ec:200) = ESP(0x004115cd:86)

DEBUG 15: multicollapse
0x004115ec:a3: ESP(0x004115ec:a3) = ESP(0x004115aa:26a) + #0xfffffffc
   0x004115ec:a3: ESP(0x004115ec:a3) = ESP(0x00411574:4b) + #0xfffffffc

DEBUG 16: addmultcollapse
0x004115ec:a3: ESP(0x004115ec:a3) = ESP(0x00411574:4b) + #0xfffffffc
   0x004115ec:a3: ESP(0x004115ec:a3) = ESP(i) + #0xfffffe94

DEBUG 17: earlyremoval
0x004115ec:200: ESP(0x004115ec:200) = ESP(0x004115cd:86)
   0x004115ec:200: **

DEBUG 18: stackptrflow
0x004115ec:a3: ESP(0x004115ec:a3) = ESP(i) + #0xfffffe94
   0x004115ec:a3: ESP(0x004115ec:a3) = ESP(i) + #0xfffffe94

DEBUG 19: storevarnode
0x004115ec:a4: *(ram,ESP(0x004115ec:a3)) = #0x4115f1
   0x004115ec:a4: s0xfffffe94(0x004115ec:a4) = #0x4115f1

DEBUG 20: loadvarnode
0x004115ec:212: u0x10000019:1(0x004115ec:212) = *(ram,ESP(0x004115ec:a3))
   0x004115ec:212: **
0x004115ec:a5: EAX(0x004115ec:a5) = call fCls3:8(free)(u0x00007a80(0x004115e6:a1),u0x10000019:1(0x004115ec:212))
   0x004115ec:a5: EAX(0x004115ec:a5) = call fCls3:8(free)(u0x00007a80(0x004115e6:a1))

DEBUG 21: heritage
0x004115ec:2fc: **
   0x004115ec:2fc: r0x0041a048(0x004115ec:2fc) = r0x0041a048(0x004115c8:2fb) [] i0x004115ec:a5:8(free)
0x004115ec:312: **
   0x004115ec:312: s0xfffffe80(0x004115ec:312) = s0xfffffe80(0x004115c8:311) [] i0x004115ec:a5:8(free)
0x004115ec:325: **
   0x004115ec:325: s0xfffffe84(0x004115ec:325) = s0xfffffe84(0x004115c8:324) [] i0x004115ec:a5:8(free)
0x004115ec:338: **
   0x004115ec:338: s0xfffffe88(0x004115ec:338) = s0xfffffe88(0x004115c8:337) [] i0x004115ec:a5:8(free)
0x004115ec:34b: **
   0x004115ec:34b: s0xfffffe8c(0x004115ec:34b) = s0xfffffe8c(0x004115c8:34a) [] i0x004115ec:a5:8(free)
0x004115ec:35e: **
   0x004115ec:35e: s0xfffffe90(0x004115ec:35e) = s0xfffffe90(0x004115c8:35d) [] i0x004115ec:a5:8(free)
0x004115ec:371: **
   0x004115ec:371: s0xfffffe94(0x004115ec:371) = s0xfffffe94(0x004115ec:a4) [] i0x004115ec:a5:8(free)
0x004115ec:384: **
   0x004115ec:384: s0xfffffe98(0x004115ec:384) = s0xfffffe98(0x004115c8:383) [] i0x004115ec:a5:8(free)
0x004115ec:397: **
   0x004115ec:397: s0xfffffe9c(0x004115ec:397) = s0xfffffe9c(0x004115c8:396) [] i0x004115ec:a5:8(free)
0x004115ec:3aa: **
   0x004115ec:3aa: s0xfffffea0(0x004115ec:3aa) = s0xfffffea0(0x004115c8:3a9) [] i0x004115ec:a5:8(free)
0x004115ec:3bd: **
   0x004115ec:3bd: s0xfffffea4(0x004115ec:3bd) = s0xfffffea4(0x004115c8:3bc) [] i0x004115ec:a5:8(free)
0x004115ec:3d0: **
   0x004115ec:3d0: s0xfffffea8(0x004115ec:3d0) = s0xfffffea8(0x004115c8:3cf) [] i0x004115ec:a5:8(free)
0x004115ec:3e3: **
   0x004115ec:3e3: s0xfffffeb0(0x004115ec:3e3) = s0xfffffeb0(0x004115c8:3e2) [] i0x004115ec:a5:8(free)
0x004115ec:3f6: **
   0x004115ec:3f6: s0xfffffebc(0x004115ec:3f6) = s0xfffffebc(0x004115c8:3f5) [] i0x004115ec:a5:8(free)
0x004115ec:409: **
   0x004115ec:409: s0xfffffec8(0x004115ec:409) = s0xfffffec8(0x004115c8:408) [] i0x004115ec:a5:8(free)
0x004115ec:41c: **
   0x004115ec:41c: s0xfffffed4(0x004115ec:41c) = s0xfffffed4(0x004115d0:8f) [] i0x004115ec:a5:8(free)
0x004115ec:42f: **
   0x004115ec:42f: s0xfffffee0(0x004115ec:42f) = s0xfffffee0(0x004115c8:42e) [] i0x004115ec:a5:8(free)
0x004115ec:442: **
   0x004115ec:442: s0xfffffeec(0x004115ec:442) = s0xfffffeec(0x004115c8:441) [] i0x004115ec:a5:8(free)
0x004115ec:455: **
   0x004115ec:455: s0xfffffef8(0x004115ec:455) = s0xfffffef8(0x004115c8:454) [] i0x004115ec:a5:8(free)
0x004115ec:468: **
   0x004115ec:468: s0xffffff04(0x004115ec:468) = s0xffffff04(0x004115c8:467) [] i0x004115ec:a5:8(free)
0x004115ec:47b: **
   0x004115ec:47b: s0xffffffd0(0x004115ec:47b) = s0xffffffd0(0x004115c8:47a) [] i0x004115ec:a5:8(free)
0x004115ec:48e: **
   0x004115ec:48e: s0xffffffdc(0x004115ec:48e) = s0xffffffdc(0x004115c8:48d) [] i0x004115ec:a5:8(free)
0x004115ec:4a1: **
   0x004115ec:4a1: s0xffffffe8(0x004115ec:4a1) = s0xffffffe8(0x004115c8:4a0) [] i0x004115ec:a5:8(free)
0x004115ec:4b4: **
   0x004115ec:4b4: s0xfffffff0(0x004115ec:4b4) = s0xfffffff0(0x004115c8:4b3) [] i0x004115ec:a5:8(free)
0x004115ec:4c7: **
   0x004115ec:4c7: s0xfffffff4(0x004115ec:4c7) = s0xfffffff4(0x004115c8:4c6) [] i0x004115ec:a5:8(free)
0x004115ec:4da: **
   0x004115ec:4da: s0xfffffff8(0x004115ec:4da) = s0xfffffff8(0x004115d6:92) [] i0x004115ec:a5:8(free)
0x004115ec:4ed: **
   0x004115ec:4ed: s0xfffffffc(0x004115ec:4ed) = s0xfffffffc(0x004115c8:4ec) [] i0x004115ec:a5:8(free)

DEBUG 22: deadcode
0x004115ec:a3: ESP(0x004115ec:a3) = ESP(i) + #0xfffffe94
   0x004115ec:a3: **
0x004115ec:312: s0xfffffe80(0x004115ec:312) = s0xfffffe80(0x004115c8:311) [] i0x004115ec:a5:8(free)
   0x004115ec:312: **
0x004115ec:325: s0xfffffe84(0x004115ec:325) = s0xfffffe84(0x004115c8:324) [] i0x004115ec:a5:8(free)
   0x004115ec:325: **
0x004115ec:338: s0xfffffe88(0x004115ec:338) = s0xfffffe88(0x004115c8:337) [] i0x004115ec:a5:8(free)
   0x004115ec:338: **
0x004115ec:34b: s0xfffffe8c(0x004115ec:34b) = s0xfffffe8c(0x004115c8:34a) [] i0x004115ec:a5:8(free)
   0x004115ec:34b: **
0x004115ec:397: s0xfffffe9c(0x004115ec:397) = s0xfffffe9c(0x004115c8:396) [] i0x004115ec:a5:8(free)
   0x004115ec:397: **
0x004115ec:3aa: s0xfffffea0(0x004115ec:3aa) = s0xfffffea0(0x004115c8:3a9) [] i0x004115ec:a5:8(free)
   0x004115ec:3aa: **
0x004115ec:3bd: s0xfffffea4(0x004115ec:3bd) = s0xfffffea4(0x004115c8:3bc) [] i0x004115ec:a5:8(free)
   0x004115ec:3bd: **
0x004115ec:409: s0xfffffec8(0x004115ec:409) = s0xfffffec8(0x004115c8:408) [] i0x004115ec:a5:8(free)
   0x004115ec:409: **
0x004115ec:42f: s0xfffffee0(0x004115ec:42f) = s0xfffffee0(0x004115c8:42e) [] i0x004115ec:a5:8(free)
   0x004115ec:42f: **
0x004115ec:442: s0xfffffeec(0x004115ec:442) = s0xfffffeec(0x004115c8:441) [] i0x004115ec:a5:8(free)
   0x004115ec:442: **
0x004115ec:455: s0xfffffef8(0x004115ec:455) = s0xfffffef8(0x004115c8:454) [] i0x004115ec:a5:8(free)
   0x004115ec:455: **
0x004115ec:468: s0xffffff04(0x004115ec:468) = s0xffffff04(0x004115c8:467) [] i0x004115ec:a5:8(free)
   0x004115ec:468: **
0x004115ec:47b: s0xffffffd0(0x004115ec:47b) = s0xffffffd0(0x004115c8:47a) [] i0x004115ec:a5:8(free)
   0x004115ec:47b: **
0x004115ec:48e: s0xffffffdc(0x004115ec:48e) = s0xffffffdc(0x004115c8:48d) [] i0x004115ec:a5:8(free)
   0x004115ec:48e: **
0x004115ec:4ed: s0xfffffffc(0x004115ec:4ed) = s0xfffffffc(0x004115c8:4ec) [] i0x004115ec:a5:8(free)
   0x004115ec:4ed: **

DEBUG 23: indirectcollapse
0x004115ec:384: s0xfffffe98(0x004115ec:384) = s0xfffffe98(0x004115c8:383) [] i0x004115ec:a5:8(free)
   0x004115ec:384: s0xfffffe98(0x004115ec:384) = s0xfffffe98(0x00411563:3d) [] i0x004115ec:a5:8(free)

DEBUG 24: propagatecopy
0x004115ec:a5: EAX(0x004115ec:a5) = call fCls3:8(free)(u0x00007a80(0x004115e6:a1))
   0x004115ec:a5: EAX(0x004115ec:a5) = call fCls3:8(free)(EAX(0x004115c8:83))

DEBUG 25: earlyremoval
0x004115ec:35e: s0xfffffe90(0x004115ec:35e) = s0xfffffe90(0x004115c8:35d) [] i0x004115ec:a5:8(free)
   0x004115ec:35e: **

DEBUG 26: earlyremoval
0x004115ec:371: s0xfffffe94(0x004115ec:371) = s0xfffffe94(0x004115ec:a4) [] i0x004115ec:a5:8(free)
   0x004115ec:371: **

DEBUG 27: indirectcollapse
0x004115ec:384: s0xfffffe98(0x004115ec:384) = s0xfffffe98(0x00411563:3d) [] i0x004115ec:a5:8(free)
   0x004115ec:384: **

DEBUG 28: propagatecopy
0x004115ec:41c: s0xfffffed4(0x004115ec:41c) = s0xfffffed4(0x004115d0:8f) [] i0x004115ec:a5:8(free)
   0x004115ec:41c: s0xfffffed4(0x004115ec:41c) = EAX(0x004115c8:83) [] i0x004115ec:a5:8(free)

DEBUG 29: earlyremoval
0x004115ec:a4: s0xfffffe94(0x004115ec:a4) = #0x4115f1
   0x004115ec:a4: **

DEBUG 30: setcasts
0x004115ec:50b: **
   0x004115ec:50b: EAX(0x004115ec:50b) = (cast) u0x10000129(0x004115ec:a5)
0x004115ec:a5: EAX(0x004115ec:a5) = call fCls3:8(free)(EAX(0x004115c8:50a))
   0x004115ec:a5: u0x10000129(0x004115ec:a5) = call fCls3:8(free)(EAX(0x004115c8:50a))

Decompilation complete

In my case, I wanted to know why the function call at 0x4115ec thinks that EAX is being passed as an argument instead of ECX.

Here is ChatGPT's explanation. And it's right! ECX will be equal to the value of EAX at the time of the call.

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Edward J. Schwartz

Computer Security Researcher

Ghidra

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