[Bug analyzer/106413] New: State explosion on va_arg when va_start is in top-level function of analysis

[dmalcolm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106413

            Bug ID: 106413
           Summary: State explosion on va_arg when va_start is in
                    top-level function of analysis
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: analyzer
          Assignee: dmalcolm at gcc dot gnu.org
          Reporter: dmalcolm at gcc dot gnu.org
  Target Milestone: ---

I accidentally introduced:
  FAIL: gcc.dg/analyzer/stdarg-3.c (test for excess errors)
in r13-1786-gb852aa7f265424; the issue is a -Wanalyzer-too-complex warning.

Looks like there's a state explosion in -fanalyzer whenever there's a loop that
calls __builtin_va_arg for the case where the va_start is in the top-level
function of the analysis (i.e. that we *don't* have a specific list of variadic
arguments).