Bumped into some code like this in our code base... which made me worried.
int foo(int a); // Forward declaration. int baz() { int result = { i
You'd have to consult your compiler documentation. This construct is not allowed in standard C or standard C++.
It's trivial to clean this up however, e.g.
int baz() { int result; { int a = dosomestuff(); result = foo(a)? 0: -1; } return result; }