[Bug gcov-profile/93757] New: [GCOV] incorrect coverage for inline function with "a?b:c" expression

[yangyibiao at hust dot edu.cn]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93757

            Bug ID: 93757
           Summary: [GCOV] incorrect coverage for inline function with
                    "a?b:c" expression
           Product: gcc
           Version: 9.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: gcov-profile
          Assignee: unassigned at gcc dot gnu.org
          Reporter: yangyibiao at hust dot edu.cn
                CC: marxin at gcc dot gnu.org
  Target Milestone: ---

$ gcov -v
gcov (GCC) 9.2.0
Copyright (C) 2019 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or 
FITNESS FOR A PARTICULAR PURPOSE.

$ gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/9.2.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /build/gcc/src/gcc/configure --prefix=/usr --libdir=/usr/lib
--libexecdir=/usr/lib --mandir=/usr/share/man --infodir=/usr/share/info
--with-bugurl=https://bugs.archlinux.org/
--enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++,d --enable-shared
--enable-threads=posix --with-system-zlib --with-isl --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-clocale=gnu --disable-libstdcxx-pch
--disable-libssp --enable-gnu-unique-object --enable-linker-build-id
--enable-lto --enable-plugin --enable-install-libiberty
--with-linker-hash-style=gnu --enable-gnu-indirect-function --enable-multilib
--disable-werror --enable-checking=release --enable-default-pie
--enable-default-ssp --enable-cet=auto gdc_include_dir=/usr/include/dlang/gdc
Thread model: posix
gcc version 9.2.0 (GCC)

$ cat small.c
static unsigned int oq[10];

static struct us { unsigned int irq; } sp[10];

static __inline__ __attribute__((always_inline)) int bar(int irq)
{
  return ((irq == 2) ? 9 : irq);
}

int main(void)
{
  int i = 0;
  struct us *s = sp;

  for (; i < 10; i++, s++)
     s->irq = bar(oq[i]);

  return 0;
}

$ gcc -O0 --coverage small.c; ./a.out; gcov small.c; cat small.c.gcov
File 'small.c'
Lines executed:100.00% of 7
Creating 'small.c.gcov'

-:    0:Source:small.c
-:    0:Graph:small.gcno
-:    0:Data:small.gcda
-:    0:Runs:1
-:    1:static unsigned int oq[10];
-:    2:
-:    3:static struct us { unsigned int irq; } sp[10];
-:    4:
-:    5:static __inline__ __attribute__((always_inline)) int bar(int irq)
-:    6:{
10*:    7:  return ((irq == 2) ? 9 : irq);
-:    8:}
-:    9:
1:   10:int main(void)
-:   11:{
1:   12:  int i = 0;
1:   13:  struct us *s = sp;
-:   14:  
11:   15:  for (; i < 10; i++, s++)
20:   16:     s->irq = bar(oq[i]);
-:   17:
1:   18:  return 0;
-:   19:}


###############################
We can find that Line #16 is wrongly marked as executed 20 times. 
When inline attribute is removed for function 'bar', the coverage is correct.