Unexpected behavior when using algorithm::trim() to remove spaces

The issue comes from boostorg/compute#817 where `boost::trim()` is invoked to sanitize OpenCL kernel arguments from preprocessor-generated strings. One of the failing cases taken directly from the boost compute repo is this:

```c++
two, pi // original string
[two, pi] // vector after split() using comma as delimiter
two // first element after trim()
p // second element after trim()
```
Here the `trim()` actually leave a leading space left of `pi` and slices one valid character on the right. One big BUT: this only happens to Linux cross-compiler targeting Android platform, downloaded from Android NDK page. Where as MSVC on Windows, GCC/Clang on Mac all run without problems. What might be the reason of this unexpected behavior?

Comece com algorithm::trim() e reproduza o exemplo de separação por vírgulas de boostorg/compute#817 usando o compilador cruzado Linux do Android NDK. Compare o comportamento com o MSVC no Windows e o GCC/Clang no macOS para isolar a causa específica da plataforma. Está concluído quando a causa estiver explicada e a saída reportada estiver corrigida sem regressões.

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