[Bug lto/87525] infinite loop generated for fread() if enabling -flto and -D_FORTIFY_SOURCE=2

[lh_mouse at 126 dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87525

Liu Hao <lh_mouse at 126 dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |lh_mouse at 126 dot com

--- Comment #9 from Liu Hao <lh_mouse at 126 dot com> ---
I reproduced this problem on Linux Mint 19 using the last two attachments. This
issue is only reproducible on i686 i.e. after `-m32` is added into FLAGS in the
build script, as I am on an x64 system.

```
lh_mouse@lhmouse-ideapad ~/Desktop $ objdump -dMintel-mneomic libFLAC.so.8.3.0 
| grep -F 'fread.constprop.5'
00002530 <fread.constprop.5>:
    2530:       eb fe                   jmp    2530 <fread.constprop.5>
    2c4e:       e8 dd f8 ff ff          call   2530 <fread.constprop.5>
    8204:       e8 27 a3 ff ff          call   2530 <fread.constprop.5>
    8b4e:       e8 dd 99 ff ff          call   2530 <fread.constprop.5>
lh_mouse@lhmouse-ideapad ~/Desktop $ gcc --version
gcc (Ubuntu 7.3.0-27ubuntu1~18.04) 7.3.0
Copyright (C) 2017 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.

lh_mouse@lhmouse-ideapad ~/Desktop $ 
```