Style and navigation in project question(?)

Hi,
I'm new in this project and for beginning  I want to figure out how to fix
this bug: https://sourceware.org/bugzilla/show_bug.cgi?id=23182
I already reproduce it and relay gdb print 'x' array wrong, but it's not a
main question.
1. Trying to figure out what function can make problems I jump into print
and slowly go back. Reading code of those function I saw style problems
like
 int x;
 ...
 if (x) ...
or
if(a==b)
   /* it's ok to be a and b equal*/
   return a+b;
Is better to not touch them or add  !=0 or {}  as said in style documents?
(this one:
https://sourceware.org/gdb/wiki/Internals%20GDB-Testsuite-Coding-Standards
)

2. Its so big and I feel a bit lost. I found those  "print"  by luck and
guess. Is there any kind of map that can help me to find eg. actually
function that look for Fortran array, and try to print it? Or what
document I miss and should read?

3. It should be first question, but em I ask those two above in right place?