https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101342
Xiaoyuan Xie <byone.heng at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|[Gcov] Wrong coverage with |[Gcov] wrong coverage for
|"for(;;a++)" loop |the function with a loop
|statement |statement
--- Comment #1 from Xiaoyuan Xie <byone.heng at gmail dot com> ---
$./gcc -v
Using built-in specs.
COLLECT_GCC=./gcc
COLLECT_LTO_WRAPPER=/home/x/project/gcc/build/install/libexec/gcc/x86_64-pc-linux-gnu/11.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../configure --prefix=/home/x/project/gcc/build/install
--enable-checking=release --enable-languages=c,c++ --disable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 11.0.0 20210105 (experimental) (GCC)
$cat test.c
static short int true_var = 1;
signed char false_var = 0;
typedef unsigned V __attribute__ ((vector_size (16)));
V
foo (unsigned x, V v)
{
do {
v %= x;
x = 1;
} while (v[1]);
return v;
}
int
main ()
{
V x = foo (5, (V) { 0, 1 });
if (x[0] || x[1] || x[2] || x[3])
__builtin_abort();
return 0;
}
$gcc -O0 --coverage test.c;./a.out;gcov test;cat test.c.gcov
-: 1:/* { dg-do run } */
-: 2:/* { dg-additional-options "-w -Wno-psabi" } */
-: 3:
-: 4:static short int true_var = 1;
-: 5:signed char false_var = 0;
-: 6:
-: 7:typedef unsigned V __attribute__ ((vector_size (16)));
-: 8:
-: 9:V
2: 10:foo (unsigned x, V v)
-: 11:{
-: 12: do {
2: 13: v %= x;
2: 14: x = 1;
2: 15: } while (v[1]);
1: 16: return v;
-: 17:}
-: 18:
-: 19:int
1: 20:main ()
-: 21:{
1: 22: V x = foo (5, (V) { 0, 1 });
1: 23: if (x[0] || x[1] || x[2] || x[3])
#####: 24: __builtin_abort();
1: 25: return 0;
-: 26:}
In my opinion, line 10 should be executed one time.
