[Bug target/121784] error: cannot tail-call: argument must be passed by copying

[xypron.glpk at gmx dot de via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121784

--- Comment #9 from Heinrich Schuchardt <xypron.glpk at gmx dot de> ---
Thanks Jakub for you detailed explanation that should help to improve the Skia
code.

As some of the tail functions modify the passed parameters (vectors r, g, b)
and then pass them to the next tail function unfortunately your workaround is
not applicable.

This is one of the functions that may be used in the tail function chain:

STAGE(matrix_3x3, const skcms_Matrix3x3* matrix) {
    const float* m = &matrix->vals[0][0];

    F R = m[0]*r + m[1]*g + m[2]*b,
      G = m[3]*r + m[4]*g + m[5]*b,
      B = m[6]*r + m[7]*g + m[8]*b;

    r = R; 
    g = G; 
    b = B; 
}