Bug#681076: gcc-4.7: gcov -f rounding problem

[Vincent Lefevre <vincent@vinc17.net>]

Package: gcc-4.7
Version: 4.7.1-4
Severity: minor

I have the following problem with gcov:

ypig:/tmp/ompfr-gcov/src> gcov -f round_prec.c
Function 'mpfr_can_round_raw'
Lines executed:100.00% of 44

Function 'mpfr_can_round'
Lines executed:100.00% of 4

Function 'mpfr_prec_round'
Lines executed:100.00% of 31

Function 'mpfr_round_raw_4'
Lines executed:95.00% of 60

Function 'mpfr_round_raw_2'
Lines executed:99.99% of 9

Function 'mpfr_round_raw'
Lines executed:100.00% of 7

File 'round_prec.c'
Lines executed:100.00% of 79
Creating 'round_prec.c.gcov'

File 'round_raw_generic.c'
Lines executed:97.37% of 76
Creating 'round_raw_generic.c.gcov'

File '/usr/include/gmp-x86_64.h'
No executable lines
Removing 'gmp-x86_64.h.gcov'

See the result for Function 'mpfr_round_raw_2': 99.99% of 9.
This is not possible! Either all the lines are executed, in which
case one should get 100%, or at most 8 lines of 9 are executed,
in which case one should get 88.89% at most.

This is reproducible on a Debian/unstable amd64 machine with MPFR
trunk r8346 by running the tools/coverage script.

-- System Information:
Debian Release: wheezy/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 3.2.0-3-amd64 (SMP w/8 CPU cores)
Locale: LANG=POSIX, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages gcc-4.7 depends on:
ii  binutils      2.22-7+local1
ii  cpp-4.7       4.7.1-4
ii  gcc-4.7-base  4.7.1-4
ii  libc6         2.13-34
ii  libgcc1       1:4.7.1-4
ii  libgmp10      2:5.0.5+dfsg-2
ii  libgomp1      4.7.1-4
ii  libitm1       4.7.1-4
ii  libmpc2       0.9-4
ii  libmpfr4      3.1.0-5
ii  libquadmath0  4.7.1-4
ii  zlib1g        1:1.2.7.dfsg-13

Versions of packages gcc-4.7 recommends:
ii  libc6-dev  2.13-34

Versions of packages gcc-4.7 suggests:
pn  binutils-gold        <none>
pn  gcc-4.7-doc          <none>
ii  gcc-4.7-locales      4.7.1-4
ii  gcc-4.7-multilib     4.7.1-4
ii  libgcc1-dbg          1:4.7.1-4
ii  libgomp1-dbg         4.7.1-4
ii  libitm1-dbg          4.7.1-4
pn  libmudflap0-4.7-dev  <none>
ii  libmudflap0-dbg      4.7.1-4
ii  libquadmath0-dbg     4.7.1-4

-- no debconf information