Function calls missing args for functions with defined arguments on QNX PPC

[mwales]

Version and Platform (required):

• Binary Ninja Version: 4.2.6455-Stable
• OS: Ubuntu
• OS Version: 22.04.5
• CPU Architecture: AMD64

Bug Description:

Looking at PPCBE QNX binaries, will often see a function call that has a
complete and correct signature in the .plt section. Occasionally in the
binary, calls to this function will not have the correct number of arguments.

libsnmp.so.1 from exhibits this problem several times in the snmp_open
function.

I often use the "Override Call Type..." feature to force binaj to show the
call with the correct number of arguments.

Also, the "Override Call Type..." GUI default signature is very vanilla. It
is always:

void calltarget()

Would be more helpful to start with the current function signature (that the
user is tyring to change), or the function signature of the target function.

Steps To Reproduce:

1. Load PPCBE QNX binary.
2. Goto the .plt section, and look for pretty standard libc functions
3. Look at callrefs to function with known signatures and see that some have
   decompilation with missing params

Expected Behavior:

Expected function signature shown for function in .plt section to be the same
as the decompiler shows for calls to the function

Screenshots/Video Recording:

Binary:

Sent binary via slack posting

Additional Information:

[fuzyll]

Binary can be found internally with search term fleshy chewy jalapeno racing.

Customer has a short-term fix for their specific problem, but this issue requires a larger effort to have a long-term fix for this platform.