[Bug target/52610] New: mpfr fails to compile when specifying CFLAGS="-O3 -mcpu=leon"

[matt at use dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52610

             Bug #: 52610
           Summary: mpfr fails to compile when specifying CFLAGS="-O3
                    -mcpu=leon"
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: target
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: matt@use.net


error when compiling MPFR 3.1.0:
debian-sparc:~/src/mpfr-3.1.0# CFLAGS="-O3 -mcpu=leon -flto" CXXFLAGS="-O3
-mcpu=v8 -flto" LDFLAGS="-flto -O3 -mcpu=v8"  ./configure
--prefix=/opt/gcc-4.7.0 --with-gnu-as --with-gnu-ld --with-gmp=/opt/gcc-4.7.0
[...]
make
[...]
libtool: compile:  gcc -DHAVE_INTTYPES_H=1 -DHAVE_STDINT_H=1
-DTIME_WITH_SYS_TIME=1 -DHAVE_LOCALE_H=1 -DHAVE_WCHAR_H=1 -DHAVE_STDARG=1
-DHAVE_SYS_TIME_H=1 -DHAVE_ALLOCA_H=1 -DHAVE_STDINT_H=1 -DHAVE_VA_COPY=1
-DHAVE_SETLOCALE=1 -DHAVE_GETTIMEOFDAY=1 -DHAVE_LONG_LONG=1 -DHAVE_INTMAX_T=1
-DMPFR_HAVE_INTMAX_MAX=1 -DMPFR_HAVE_FESETROUND=1 -DHAVE_DENORMS=1
-DHAVE_FLOOR=1 -DHAVE_CEIL=1 -DMPFR_USE_THREAD_SAFE=1 -DLT_OBJDIR=\".libs/\"
-DHAVE_ATTRIBUTE_MODE=1 -DHAVE___GMPN_ROOTREM=1 -DHAVE___GMPN_SBPI1_DIVAPPR_Q=1
-I. -I/opt/gcc-4.7.0/include -O3 -mcpu=leon -flto -MT cmp.lo -MD -MP -MF
.deps/cmp.Tpo -c cmp.c  -fPIC -DPIC -o .libs/cmp.o
/tmp/ccjJFPW2.s: Assembler messages:
/tmp/ccjJFPW2.s:241: Error: Hardware capability "mul32" not enabled for "smul".
make[2]: *** [cmp.lo] Error 1

When I try to add -Av8 to CFLAGS, I get this error:
<command-line>:0:1: error: missing '(' after predicate

I have a qemu-sparc virtual machine based on Debian/Sarge I can provide that
reproduces the problem. I'll work on attaching a pre-processed example.