Extended Description

Hi

The source file attached produce different codegen behaviour for X86_64 at optimization levels -O2, -O3, -Os with -g enabled and disabled.

Interesting note here is that disassembly of code at one -opt level vary a lot from code generated at different -opt level.

I have attached the source file, code generated at -O2 with/without -g option.

Steps to reproduced in X86_64 linux.

clang++ -c -g -O2 -Wno-everything -I/headers/of/csmith source.cpp -o di

clang++ -c -O2 -Wno-everything -I/headers/of/csmith source.cpp -o nodi

objdump -d -j .text nodi > hide1
objdump -d -j .text di > hide2

colordiff hide1 hide2 || diff hide1 hide2

As these are randomly generated, the reducing to these to minimum test case is quite difficult. I'm working on that.

Anyone have thoughts on it? Please reply
Thanks