[clang] [openmp] [llvm] [clang-tools-extra] Fix Issue #76121 [OpenMP] [Flang] Program crashes at runtime (PR #76122)

[via llvm-commits]

shivaramaarao wrote:

These cmov instructions load the operand irrespective of condition satisfaction. 

=>  cmpq    $4, %rax  
=>  cmovnsq 24(%r11), %r9   

     here r11 is 0 and 24(0) will be loaded even if argc < 4 and hence we get this crash. if we pass the address of argv, we will get a valid address to load.

   I think we need to add a check for argc <=0 in this function. But, there may be performance implications with this extra check.


https://github.com/llvm/llvm-project/pull/76122