date_default_timezone_set() — internals

date_default_timezone_set() — internals

Where it lives

• Signature: src/builtins/system/date_default_timezone_set.rs
• Lowering: src/codegen/lower_inst/builtins/system.rs:84 (lower_date_default_timezone_set)
• Function symbol: lower_date_default_timezone_set()

Lowering notes

• Lowers date_default_timezone_set(timezoneId) through the shared runtime helper.
• Materializes the identifier string into the registers the helper reads (ptr/len in
• x1/x2 on ARM64, rax/rdx on x86_64), then __rt_date_default_timezone_set
• applies it via libc putenv+tzset and returns PHP true in the integer-result register.

Runtime helpers

The following runtime helpers are referenced:

• __rt_date_default_timezone_set
• __rt_microtime
• __rt_microtime_mixed
• __rt_microtime_str

Signature summary

function date_default_timezone_set(string $timezoneId): bool

What the type checker enforces

• Arity: takes exactly 1 argument.

Eval interpreter (magician)

• Declaration: crates/elephc-magician/src/interpreter/builtins/time/date_default_timezone_set.rs (eval_builtin!)
• Dispatch hooks: direct, values

Cross-references

• User reference for date_default_timezone_set()