[Bug c/51846] New: Compiled programs suffer from infinite recursion when using -finstrument-functions with optimizations

[daniel at totalueberwachung dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51846

             Bug #: 51846
           Summary: Compiled programs suffer from infinite recursion when
                    using -finstrument-functions with optimizations
    Classification: Unclassified
           Product: gcc
           Version: 4.5.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: daniel@totalueberwachung.de


Created attachment 26313
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=26313
Testcase

While trying to debug a different issue I've been having with instrumentation
I've run into this problem. It seems that with any sort of optimization enabled
the compiler doesn't obey the no_instrument_function attribute. Attached is a
small testcase. The output I get when compiling with and without optimization
or instrumentation is this:

$ gcc -O0 -o main main.c 
$ ./main 
Start
End
$ gcc -Os -o main main.c 
$ ./main 
Start
End
$ gcc -Os -finstrument-functions -o main main.c 
$ ./main 
Segmentation fault
$ gcc -O0 -finstrument-functions -o main main.c 
$ ./main 
-> 0x400674 0x7fcbd75eb09d
Start
-> 0x400652 0x4006a1
<- 0x400652 0x4006a1
End
<- 0x400674 0x7fcbd75eb09d

Attached to a debugger or when looking at the assembly you can easily see that
the __cyg_profile_func_enter function has a call to itself when compiled with
any optimization setting other than O0.