[Bug target/109713] New: [14 Regression] gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void function [-Werror=return-type] since r14-406-gbff7c773864479

[Bug target/109713] New: [14 Regression] gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void function [-Werror=return-type] since r14-406-gbff7c773864479

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109713

            Bug ID: 109713
           Summary: [14 Regression] gcc/config/riscv/sync.md:66:1: error:
                    control reaches end of non-void function
                    [-Werror=return-type] since r14-406-gbff7c773864479
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marxin at gcc dot gnu.org
                CC: patrick at rivosinc dot com
  Target Milestone: ---
              Host: x86_64-linux-gnu
            Target: riscv64-unknown-linux-gnu

Since the revision I see:

[ 5046s] ../../gcc/config/riscv/sync.md: In function 'const char*
output_479(rtx_def**, rtx_insn*)':
[ 5046s] ../../gcc/config/riscv/sync.md:66:1: error: control reaches end of
non-void function [-Werror=return-type]
[ 5046s]    66 |   [(set (attr "length") (const_int 4))])
[ 5046s]       | ^
[ 5046s] cc1plus: some warnings being treated as errors

[Bug target/109713] [14 Regression] gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void function [-Werror=return-type] since r14-406-gbff7c773864479

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109713

--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
The following generated code reports the warning:

static const char *
output_491 (rtx *operands ATTRIBUTE_UNUSED, rtx_insn *insn ATTRIBUTE_UNUSED)
{
#line 53 "/home/marxin/Programming/gcc/gcc/config/riscv/sync.md"
{
    enum memmodel model = (enum memmodel) INTVAL (operands[1]);
    model = memmodel_base (model);
    if (model == MEMMODEL_SEQ_CST)
        return "fence\trw,rw";
    else if (model == MEMMODEL_ACQ_REL)
        return "fence.tso";
    else if (model == MEMMODEL_ACQUIRE)
        return "fence\tr,rw";
    else if (model == MEMMODEL_RELEASE)
        return "fence\trw,w";
  }
}

[Bug target/109713] [14 Regression] gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void function [-Werror=return-type] since r14-406-gbff7c773864479

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109713

--- Comment #2 from Martin Liška <marxin at gcc dot gnu.org> ---
So something like this can fix it:

diff --git a/gcc/config/riscv/sync.md b/gcc/config/riscv/sync.md
index ba132d8a1ce..206adcfec3c 100644
--- a/gcc/config/riscv/sync.md
+++ b/gcc/config/riscv/sync.md
@@ -61,6 +61,8 @@ (define_insn "mem_thread_fence_1"
        return "fence\tr,rw";
     else if (model == MEMMODEL_RELEASE)
        return "fence\trw,w";
+    else
+        gcc_unreachable ();
   }
   [(set (attr "length") (const_int 4))])

[Bug target/109713] [14 Regression] gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void function [-Werror=return-type] since r14-406-gbff7c773864479

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109713

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2023-05-03
             Status|UNCONFIRMED                 |NEW

[Bug target/109713] [14 Regression] gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void function [-Werror=return-type] since r14-406-gbff7c773864479

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109713

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
8 spaces -> tab.

[Bug target/109713] [14 Regression] gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void function [-Werror=return-type] since r14-406-gbff7c773864479

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109713

--- Comment #4 from Martin Liška <marxin at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #3)
> 8 spaces -> tab.

May I commit it as obvious with the change?

[Bug target/109713] [14 Regression] gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void function [-Werror=return-type] since r14-406-gbff7c773864479

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109713

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Yes, preapproved.

[Bug target/109713] [14 Regression] gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void function [-Werror=return-type] since r14-406-gbff7c773864479

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109713

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |14.0

[Bug target/109713] [14 Regression] gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void function [-Werror=return-type] since r14-406-gbff7c773864479

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109713

--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Martin Liska <marxin@gcc.gnu.org>:

https://gcc.gnu.org/g:4bd434fbfc7865961a8e10d7e9601b28765ce7be

commit r14-432-g4bd434fbfc7865961a8e10d7e9601b28765ce7be
Author: Martin Liska <mliska@suse.cz>
Date:   Wed May 3 16:35:26 2023 +0200

    riscv: fix error: control reaches end of non-void function

    Fixes:
    gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void
function [-Werror=return-type]
    66 |   [(set (attr "length") (const_int 4))])
       | ^

            PR target/109713

    gcc/ChangeLog:

            * config/riscv/sync.md: Add gcc_unreachable to a switch.

[Bug target/109713] [14 Regression] gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void function [-Werror=return-type] since r14-406-gbff7c773864479

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109713

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

--- Comment #7 from Martin Liška <marxin at gcc dot gnu.org> ---
Fixed now.

[Bug target/109713] [14 Regression] gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void function [-Werror=return-type] since r14-406-gbff7c773864479

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109713

--- Comment #8 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-13 branch has been updated by Patrick O'Neill
<poneill@gcc.gnu.org>:

https://gcc.gnu.org/g:1e9180b3298def6c01d9055d558fdb52231f8d2d

commit r13-7674-g1e9180b3298def6c01d9055d558fdb52231f8d2d
Author: Martin Liska <mliska@suse.cz>
Date:   Wed May 3 16:35:26 2023 +0200

    riscv: fix error: control reaches end of non-void function

    Fixes:
    gcc/config/riscv/sync.md:66:1: error: control reaches end of non-void
function [-Werror=return-type]
    66 |   [(set (attr "length") (const_int 4))])
       | ^

            PR target/109713

    gcc/ChangeLog:

            * config/riscv/sync.md: Add gcc_unreachable to a switch.