Wrong output of function log inside loop

[beriarue]

Description

In the code below, the function log should be executed for 5 times, and the sentence res is "0x00000000" should be printed for 5 times. However, such sentence is only printed once during the runtime.

def main() -> u32 {
    u32 res = 0;
    for u32 i in 0..5 {
        log("res is {}", res);
    }
    return res;
}

Expected result:

...
res is "0x00000000"
res is "0x00000000"
res is "0x00000000"
res is "0x00000000"
res is "0x00000000"
...

Environment

• Compiler version: 0.8.7
• Operating system: Ubuntu 22.04

Steps to Reproduce

Save the buggy code into buggy.zok. Run the following commands from CLI:

# compile
zokrates compile --debug -i buggy.zok
zokrates setup
zokrates compute-witness
zokrates generate-proof
zokrates verify

You would see the following output, which is different from the expected result shown before.

...
res is "0x00000000"
...