# PrecompileTools and --trace-compile
**URL:** https://discourse.julialang.org/t/precompiletools-and-trace-compile/109067
**Category:** Performance
**Tags:** precompilation
**Created:** [January 21, 2024, 6:41am UTC](https://discourse.julialang.org/t/precompiletools-and-trace-compile/109067 "2024-01-21T06:41:04Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@mchitre](https://discourse.julialang.org/u/mchitre)
#### Post date: [January 21, 2024, 6:41am UTC](https://discourse.julialang.org/t/precompiletools-and-trace-compile/109067/1 "2024-01-21T06:41:04Z")
I have a simple package `Test1`:
```julia
module Test1
f1(x) = x + 1
f2(x) = f1(2x)
f3(x) = f1(3x)
using PrecompileTools
@compile_workload begin
f2(1.2)
end
end # module
```
I load and precompile the package in an environment. I then run:
```julia
julia --trace-compile stderr -e 'using Test1; Test1.f2(1.2); Test1.f1(1.2);'
```
I get the output:
```julia
:
precompile(Tuple{typeof(Test1.f2), Float64})
precompile(Tuple{typeof(Test1.f1), Float64})
```
Two questions:
1. I would have expected the method `Test1.f2(::Float64)` to have been cached at precompilation. Why do I get a `precompile(...)` statement for `Test1.f2` in the trace when I run this?
2. I would have expected the method `Test1.f1(::Float64)` to have been compiled when I run `f2(1.2)`, so why do I get a `precompile(...)` statement in the trace for `Test1.f1` when I run the `Test1.f1(1.2)` statement?
If I add an explicit `precompile(f2, (Float64,))` to `Test1`, the precompile statment for `f2` is no longer shown on execution, as one would expect. But the one for `f1` still appears, although `f1` should have been precompiled due to precompilation of `f2`.
---
### Author:  [@Benny](https://discourse.julialang.org/u/Benny)
#### Post date: [January 21, 2024, 7:12am UTC](https://discourse.julialang.org/t/precompiletools-and-trace-compile/109067/2 "2024-01-21T07:12:32Z")
> [@mchitre](#):
>
> If I add an explicit `precompile(f2, (Float64,))` to `Test1`, the precompile statment for `f2` is no longer shown on execution, as one would expect. But the one for `f1` still appears, although `f1` should have been precompiled due to precompilation of `f2`.
`f2` being compiled when `f1` isn’t can be explained by `f1` being inlined into `f2` after methods were dispatched at compile-time. You don’t need to independently compile a method if it’s always inlined. Verify the absence of a `f1` call in `@code_llvm f2(1.2)`.
---
### Author:  [@mchitre](https://discourse.julialang.org/u/mchitre)
#### Post date: [January 21, 2024, 7:30am UTC](https://discourse.julialang.org/t/precompiletools-and-trace-compile/109067/3 "2024-01-21T07:30:32Z")
Fair enough. The precompile statements disappear if I annotate `@noinline` for all 3 of the functions.
---
### Author:  [@Benny](https://discourse.julialang.org/u/Benny)
#### Post date: [January 21, 2024, 3:26pm UTC](https://discourse.julialang.org/t/precompiletools-and-trace-compile/109067/4 "2024-01-21T15:26:22Z")
I wouldn’t mark an offhand comment as a solution, it lowers the visibility of the thread for people who could explain the unexpected behavior for PrecompileTools, which is the primary topic.