object 'Cdqrls' not found when building R packages using devtools

Question

I got an error as the title shows

Error: object 'Cdqrls' not found

I use devtools for building R packages, and one function in my current package, I used

.Call(Cdqrls, x[, id1, drop=FALSE] * w,  w * z, epsilon)

and also includes a lm.c file in the src folder, which includes:

...
SEXP Cdqrls(SEXP x, SEXP y, SEXP tol)
{
    SEXP ans, ansnames;
    SEXP qr, coefficients, residuals, effects, pivot, qraux;
    int n, ny = 0, p, rank, nprotect = 4, pivoted = 0;
    double rtol = asReal(tol), *work;
...

directly copied from R source files. When I used load_all() in devtools, it compiles shared objects in src/ (I checked that works well) with new files: lm.o and MyPkgName.so. However, from the wiki of devtools, I found that

load_all ignores the package NAMESPACE

If working properly, I think by running some functions, I am able to update the NAMESPACE file to contain useDynLib(MyPkgName, Cdqrls). Is that correct? I think in that way the error may disappear... Any suggestions are greatly appreciated!

Update

According to @mnel and this post, it seems that using @useDynLib should work. However, the function I used .Call() is NOT documented, and there are several functions that used .Call so I personally do not wanna document them as they're not used for end-users. Thus, where shall I put @useDynLib?

Answer 1

The answer is to use @useDynLib PkgName Routine1 Routine2 using roxygen2, so that once running document() function in devtools the NAMESPACE file will contain useDynLib(PkgName,Routine1,Routine2), which will work perfectly.