[Bug bootstrap/95805] New: [11 regression] gcc/recog.h:301:30: error: too many arguments to function call, expected 1, have 2

[gerald at pfeifer dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95805

            Bug ID: 95805
           Summary: [11 regression] gcc/recog.h:301:30: error: too many
                    arguments to function call, expected 1, have 2
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gerald at pfeifer dot com
                CC: rsandifo at sources dot redhat.com
  Target Milestone: ---

Created attachment 48766
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48766&action=edit
Relevant portion of the log file

This started in the 24 hours leading up to 2020-06-18-16:40UTC.

I am wondering whether this was triggered by 

commit 4e49b994de060d4a6c9318d0ed52ef038153426e
Author: Richard Sandiford <richard.sandiford@arm.com>
Date:   Wed Jun 17 17:45:29 2020 +0100

    recog: Tweak insn_gen_fn::operator() definition

    Fixes a “left operand of comma has no effect” warning that some were
    seeing.  Also fixes a spurious ellipsis that Jonathan Wakely pointed
    out.

    2020-06-17  Richard Sandiford  <richard.sandiford@arm.com>

    gcc/
            * coretypes.h (first_type): New alias template.
            * recog.h (insn_gen_fn::operator()): Use it instead of a decltype.
            Remove spurious “...” and split the function type out into a
typedef