Trying to install rTandem on Debian Sid.  I get this error:

g++  -I/usr/share/R/include -DNDEBUG  -I"/home/hatta/R/x86_64-pc-linux-gnu-library/3.4/Rcpp/include"    -fpic  -g -O2 -fdebug-prefix-map=/build/r-base-PbieFK/r-base-3.4.4=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -g  -c loadmspectrum.cpp -o loadmspectrum.o
loadmspectrum.cpp: In member function ‘virtual bool loadpkl::get(mspectrum&)’:
loadmspectrum.cpp:685:18: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
     if(pValue != '\0' && strlen(pValue) > 2) {
                  ^~~~
loadmspectrum.cpp: In member function ‘virtual bool loaddta::get(mspectrum&)’:
loadmspectrum.cpp:875:18: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
     if(pValue != '\0' && strlen(pValue) > 2) {
                  ^~~~
make: *** [/usr/lib/R/etc/Makeconf:168: loadmspectrum.o] Error 1
ERROR: compilation failed for package ‘rTANDEM’
* removing ‘/home/hatta/R/x86_64-pc-linux-gnu-library/3.4/rTANDEM’

This is my sessionInfo():

> sessionInfo()
R version 3.4.4 (2018-03-15)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Debian GNU/Linux buster/sid

Matrix products: default
BLAS: /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.8.0
LAPACK: /usr/lib/x86_64-linux-gnu/lapack/liblapack.so.3.8.0

locale:
 [1] LC_CTYPE=en_US.utf8       LC_NUMERIC=C             
 [3] LC_TIME=en_US.utf8        LC_COLLATE=en_US.utf8    
 [5] LC_MONETARY=en_US.utf8    LC_MESSAGES=en_US.utf8   
 [7] LC_PAPER=en_US.utf8       LC_NAME=C                
 [9] LC_ADDRESS=C              LC_TELEPHONE=C           
[11] LC_MEASUREMENT=en_US.utf8 LC_IDENTIFICATION=C      

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] BiocInstaller_1.28.0

loaded via a namespace (and not attached):
[1] compiler_3.4.4 tools_3.4.4   

For anyone else who has this problem, the solution I found was:

echo -e "CC=gcc-6\nCXX=G++-6" > ~/.R/Makevars