I am attempting to typeset a document using newtxmath.sty using the libertine and frenchmath options. The minimal example below throws 53 errors, all of the "missing control sequence inserted" or "undefined control sequence" variety. For example,

\usepackage[frenchmath, libertine]{newtxmath}
Hello world 

The above typesets the following:![enter image description here

This is the kind of error I'm getting:

/usr/local/texlive/2019/texmf-dist/tex/latex/newtx/newtxmath.sty:2089: Missing control sequence inserted. \inaccessible l.2089 ...MathSymbol{A}{\mathalpha}{operators}{65}

Removing the frenchmath option for newtxmath solves the issue, but I'd prefer to typeset with that option enabled. I checked to see if there was some difference between my version of the .sty file and the most recent and there is not.

  • 2
    It's a bug, apparently. Changing the definition of \re@DeclareMathSymbol to \def\re@DeclareMathSymbol#1#2#3#4{% \if\relax\noexpand#1\let#1=\undefined \fi \DeclareMathSymbol{#1}{#2}{#3}{#4}} (for me it's on line 578 of newtxmath.sty) seems to work (you need to make a copy of newtxmath.sty though). – Phelype Oleinik Jan 11 at 1:00
  • 1
    Link to this issue sent to the package author (at the e-mail found in the README file). – quark67 Jan 11 at 1:22
  • 4
    I'm voting to close this question as off-topic because the issue has been solved with version 1.624 of the package, released 2020/01/25 – egreg Apr 4 at 21:17