[llvm-bugs] [Bug 50775] New: [LLVM-COV] Using "setjmp" statement leads wrong coverage

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=50775

            Bug ID: 50775
           Summary: [LLVM-COV] Using "setjmp" statement leads wrong
                    coverage
           Product: Runtime Libraries
           Version: 11.0
          Hardware: PC
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: libprofile library
          Assignee: unassignedbugs at nondot.org
          Reporter: cnwy1996 at outlook.com
                CC: llvm-bugs at lists.llvm.org

$ clang -v
clang version 11.0.0
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /home/wangyang/llvm-project/build/bin
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.5.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.5.0
Candidate multilib: .;@m64
Selected multilib: .;@m64

$ cat test.c
#include <setjmp.h>
#include <stdlib.h>

jmp_buf env;
extern void sub(void);
int called;
__attribute__((__noinline__)) int sjtest() {
  int i;
  if (setjmp(env))
    return 99;

  for (i = 0; i < 10; i++)
    sub();
  printf("Executed!\n");
  longjmp(env, 1);
}

__attribute__((__noinline__)) void sub(void) { called++; }


int main(void) {
  if (sjtest() != 99 || called != 10)
    abort();
  exit(0);
}

$ clang -w -O0 -g -fcoverage-mapping -fprofile-instr-generate=test.profraw
test.c; ./a.out; llvm-profdata merge test.profraw -o test.profdata; llvm-cov
show a.out -instr-profile=test.profdata test.c > test.lcov; cat test.lcov
Executed!
    1|       |#include <setjmp.h>
    2|       |#include <stdlib.h>
    3|       |
    4|       |jmp_buf env;
    5|       |extern void sub(void);
    6|       |int called;
    7|      1|__attribute__((__noinline__)) int sjtest() {
    8|      1|  int i;
    9|      1|  if (setjmp(env))
   10|      1|    return 99;
   11|      0|
   12|     10|  for (i = 0; i < 10; i++)
   13|     10|    sub();
   14|      0|  printf("Executed!\n");
   15|      0|  longjmp(env, 1);
   16|      0|}
   17|       |
   18|     10|__attribute__((__noinline__)) void sub(void) { called++; }
   19|       |
   20|       |
   21|      1|int main(void) {
   22|      1|  if (sjtest() != 99 || called != 10)
   23|      0|    abort();
   24|      1|  exit(0);
   25|      1|}

We can see that line 14 and 15 were wrongly marked as unexecuted, and the
coverage of line 12 should be 11.

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20210620/25b968cc/attachment.html>