Add build tag sqlite_math_functions

[nkt-dk]

Add build tag sqlite_math_functions to enable built-in scalar math functions using compiler flag SQLITE_ENABLE_MATH_FUNCTIONS. For reference: https://www.sqlite.org/lang_mathfunc.html.

I also updated the readme file, please let me know if you have any comments

[lggruspe]

I think this extension requires linking to math.h:

#cgo LDFLAGS: -lm

[nkt-dk]

Thank you for the feedback, I think you are correct. I updated the PR and added the linker flag

[rittneje]

Please also update the GitHub merge gate to include this new tag in the "Tags: full" step.

go-sqlite3/.github/workflows/go.yaml

Lines 46 to 47 in bedc298

	- name: 'Tags: full'
	run: go-acc . -- -race -v -tags "sqlite_allow_uri_authority sqlite_app_armor sqlite_foreign_keys sqlite_fts5 sqlite_icu sqlite_introspect sqlite_json sqlite_preupdate_hook sqlite_secure_delete sqlite_see sqlite_stat4 sqlite_trace sqlite_userauth sqlite_vacuum_incr sqlite_vtable sqlite_unlock_notify sqlite_column_metadata"

It would also be helpful to include a unit test (with the same build tag) to verify that the SQLite math functions are compiled in. I don't think it's necessary to cover all of them, just pick one to ensure the build options are being set properly. https://www.sqlite.org/lang_mathfunc.html

[bearbin]

@nkt-dk Just giving you a ping on this, would be good to get the build flag in sometime :)

[nkt-dk]

Hi @bearbin,
I did not have much time lately but @lggruspe continued this fix and create a new PR here: #1059 Thus I think my PR can be closed and we continue in 1059?

[rittneje]

superseded by #1059