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The merged PR #3 makes ldrgen generate a spurious "break" label along each while statement. Such a label seems to be related to some exit condition/statement for the loop which, however, does not exist.
Snippet of such a generation:

while (i < N) {
    v_29 = *(arr + i);
    v_19 += ! ((unsigned int)v_27 / (v_29 + 660U));
    i ++;
}
while_0_break: ;

This not a dreadful issue, but it would be better not to generate such useless labels (and respective; statements).

Hypothesis on the problem

The problem seems to be related to the -simplify-cfg machinery of Frama-C, which ldrgen seems to activate in some unclear way.
Indeed, the Frama-C's pretty-printer typically recognizes code patterns like:

while(1) { if (!cond) break; ... }

and turns them into:

while (cond) { ... }

When -simplify-cfg is activated and has called on a code, the first code pattern is turned into:

while(1) { if (!cond) goto while_0_break; ... } while_0_break: ;

and the pretty-printer goes on with its job but does not remove the label as it would be difficult to do in general.

This seems the most plausible explanation of the issue, at least this is what the senior devs of Frama-C told me, but I haven't found any evident mention of -simplify-cfg nor programmatic use of it in ldrgen.

Occasionally we generate code containing an expression inff which is then rejected by the C compiler when we try to compile the generated function. Presumably some randomly generated floating point constant is an infinity. We should only generate finite constants.