[Bug rtl-optimization/64323] New: LRA: ICE when compiling newlib for ARM.

[Hale.Wang at arm dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64323

            Bug ID: 64323
           Summary: LRA: ICE when compiling newlib for ARM.
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: Hale.Wang at arm dot com

Created attachment 34287
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34287&action=edit
This temp file is generated from newlib/newlib/libc/stdlib/dtoa.c.

When compiling the newlib stdlib for ARM, GCC 5.0 reported:

newlib/newlib/libc/stdlib/dtoa.c:862:1: error: unable to generate reloads for:
(insn 2301 287 2302 16 (set (reg:CCFP 101 vfpcc)
        (compare:CCFP (reg:DF 217 [ D.6454 ])
            (const_double:DF 0.0 [0x0.0p+0])))
.../newlib/newlib/libc/stdlib/dtoa.c:282 679 {*cmpdf_vfp}
     (nil))

/work/tools/gcc-arm-none-eabi-5_0-2014q4-20141211/src/newlib/newlib/libc/stdlib/dtoa.c:862:1:
internal compiler error: in curr_insn_transform, at lra-constraints.c:3383

The command line is:
arm-none-eabi-gcc -marm  -O2  -mfloat-abi=hard dtoa.i

I have attached the temp file 'dtoa.i'. If I added the -mno-lra option, there
was no error.