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# cblas_xerbla

The default error handler for BLAS routines.

```
void cblas_xerbla(__LAPACK_int p, char *rout, char *form, ...);
```

## Parameters

`p`

The position of the invalid parameter

`rout`

The name of the routine that generated this error.

`form`

A format string describing the error.

## Discussion

Add any additional parameters required for the format string.

> Important:
> Apple provides the BLAS and LAPACK libraries under the Accelerate framework to be in line with LAPACK 3.9.1. Starting with iOS 26, iPadOS 26, macOS 26, tvOS 26, visionOS 26, and watchOS 26, the libraries are in line with LAPACK 3.12.0. These new interfaces provide additional functionality, as well as a new ILP64 interface. To use the new interfaces, define `ACCELERATE_NEW_LAPACK` before including the Accelerate or vecLib headers. For ILP64 interfaces, also define `ACCELERATE_LAPACK_ILP64`. For Swift projects, specify `ACCELERATE_NEW_LAPACK=1` and `ACCELERATE_LAPACK_ILP64=1` as preprocessor macros in Xcode build settings under Apple Clang - Preprocessing > Preprocessor Macros.

---

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