[Bug debug/107356] New: -fcompare-debug failure (length) with -fsanitize=undefined

[Bug debug/107356] New: -fcompare-debug failure (length) with -fsanitize=undefined

[zsojka at seznam dot cz]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107356

            Bug ID: 107356
           Summary: -fcompare-debug failure (length) with
                    -fsanitize=undefined
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Keywords: compare-debug-failure
          Severity: normal
          Priority: P3
         Component: debug
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zsojka at seznam dot cz
                CC: aoliva at gcc dot gnu.org
  Target Milestone: ---
              Host: x86_64-pc-linux-gnu

Created attachment 53755
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53755&action=edit
reduced testcase

Maybe related to PR107183

Compiler output:
$ x86_64-pc-linux-gnu-gcc -O -fsanitize=undefined -fcompare-debug testcase.c
-save-temps
x86_64-pc-linux-gnu-gcc: error: testcase.c: '-fcompare-debug' failure (length)

$ diff -u *gkd
--- a-testcase.c.gkd    2022-10-22 10:58:05.863774954 +0200
+++ a-testcase.gk.c.gkd 2022-10-22 10:58:05.893774995 +0200
@@ -15,21 +15,21 @@
         (nil)))
 (note # 0 0 NOTE_INSN_PROLOGUE_END)
 (note # 0 0 NOTE_INSN_FUNCTION_BEG)
+(insn # 0 0 2 (set (reg:SF 8 st)
+        (const_double:SF 0.0 [0x0.0p+0])) "testcase.c":6:18# {*movsf_internal}
+     (expr_list:REG_EQUIV (const_double:SF 0.0 [0x0.0p+0])
+        (nil)))
 (insn # 0 0 2 (set (reg:XF 8 st)
         (mem/c:XF (plus:DI (reg/f:DI 7 sp)
                 (const_int 16 [0x10])) [ f+0 S16 A128])) "testcase.c":6:18#
{*movxf_internal}
      (expr_list:REG_EQUIV (mem/c:XF (reg/f:DI 16 argp) [ f+0 S16 A128])
         (nil)))
-(insn # 0 0 2 (set (reg:SF 8 st)
-        (const_double:SF 0.0 [0x0.0p+0])) "testcase.c":6:18# {*movsf_internal}
-     (expr_list:REG_EQUIV (const_double:SF 0.0 [0x0.0p+0])
-        (nil)))
 (insn # 0 0 2 (set (reg:CCFP 17 flags)
         (unspec:CCFP [
                 (compare:CCFP (reg:XF 8 st)
                     (reg:XF 9 st(1)))
             ] UNSPEC_NOTRAP)) "testcase.c":6:18# {*cmpiuxf_i387}
-     (expr_list:REG_DEAD (reg:XF 8 st)
+     (expr_list:REG_DEAD (reg:XF 8 st [91])
         (nil)))
 (insn # 0 0 2 (set (reg:XF 8 st)
         (reg:XF 8 st)) "testcase.c":6:18# {*movxf_internal}


$ x86_64-pc-linux-gnu-gcc -v
Using built-in specs.
COLLECT_GCC=/repo/gcc-trunk/binary-latest-amd64/bin/x86_64-pc-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-r13-3440-20221021201743-g4cfdaeb2755-checking-yes-rtl-df-extra-nobootstrap-amd64/bin/../libexec/gcc/x86_64-pc-linux-gnu/13.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++
--enable-valgrind-annotations --disable-nls --enable-checking=yes,rtl,df,extra
--disable-bootstrap --with-cloog --with-ppl --with-isl
--build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu
--target=x86_64-pc-linux-gnu --with-ld=/usr/bin/x86_64-pc-linux-gnu-ld
--with-as=/usr/bin/x86_64-pc-linux-gnu-as --disable-libstdcxx-pch
--prefix=/repo/gcc-trunk//binary-trunk-r13-3440-20221021201743-g4cfdaeb2755-checking-yes-rtl-df-extra-nobootstrap-amd64
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 13.0.0 20221021 (experimental) (GCC)

[Bug target/107356] -fcompare-debug failure (length) with -fsanitize=undefined

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107356

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
long double uses x87 and reg-stack.cc still.  So a target issue.