Removing gathered environment results in wrong nesting in latexdiff output

[lucainnocenti]

Consider the following two files:

old.tex:

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\begin{equation}
\begin{gathered}
    a \\ b
\end{gathered}
\end{equation}

\end{document}

and new.tex:

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\end{document}

Running latexdiff old.tex new.tex > diff.tex produces (with latexdiff 1.2.0, Windows 10):

diff.tex:

\documentclass{article}
%DIF LATEXDIFF DIFFERENCE FILE
%DIF DEL .\test_old.tex   Tue Mar 21 16:11:14 2017
%DIF ADD .\test_new.tex   Tue Mar 21 16:11:13 2017
\usepackage{amsmath}
%DIF PREAMBLE EXTENSION ADDED BY LATEXDIFF
%DIF UNDERLINE PREAMBLE %DIF PREAMBLE
\RequirePackage[normalem]{ulem} %DIF PREAMBLE
\RequirePackage{color}\definecolor{RED}{rgb}{1,0,0}\definecolor{BLUE}{rgb}{0,0,1} %DIF PREAMBLE
\providecommand{\DIFadd}[1]{{\protect\color{blue}\uwave{#1}}} %DIF PREAMBLE
\providecommand{\DIFdel}[1]{{\protect\color{red}\sout{#1}}}                      %DIF PREAMBLE
%DIF SAFE PREAMBLE %DIF PREAMBLE
\providecommand{\DIFaddbegin}{} %DIF PREAMBLE
\providecommand{\DIFaddend}{} %DIF PREAMBLE
\providecommand{\DIFdelbegin}{} %DIF PREAMBLE
\providecommand{\DIFdelend}{} %DIF PREAMBLE
%DIF FLOATSAFE PREAMBLE %DIF PREAMBLE
\providecommand{\DIFaddFL}[1]{\DIFadd{#1}} %DIF PREAMBLE
\providecommand{\DIFdelFL}[1]{\DIFdel{#1}} %DIF PREAMBLE
\providecommand{\DIFaddbeginFL}{} %DIF PREAMBLE
\providecommand{\DIFaddendFL}{} %DIF PREAMBLE
\providecommand{\DIFdelbeginFL}{} %DIF PREAMBLE
\providecommand{\DIFdelendFL}{} %DIF PREAMBLE
%DIF END PREAMBLE EXTENSION ADDED BY LATEXDIFF

\begin{document}

 \DIFdelbegin \begin{displaymath}
\DIFdel{\begin{gathered}
    a }\\ \DIFdel{b
\end{gathered}
}\end{displaymath}
%DIFAUXCMD
%DIFDELCMD < 

%DIFDELCMD <  %%%
\DIFdelend\end{document}

Compiling diff.tex results in compilation errors, most likely due to way the gathered environment is split at the linebreak.

Is there a workaround for this?

[alexpacini]

+1. I have the same issue. A workaround is to surround manually with a blue color group (or a single \DIFdel / \DIFadd), but is quite annoying.