Commands for reproducing CRAN r-devel-linux-x86_64-debian-gcc compiler warnings with Docker

gistfile1.txt

docker run --rm -ti rhub/debian-gcc-devel

echo -e "
#include <stdlib.h>
#include <string.h>

char* create_string(const char* value) {
  // strlen doesn't count null terminator
  int n = strlen(value) + 1;
  char* str = (char *) malloc(n);
  strncpy(str, value, n);
  return str;
}" > create_string.c

gcc -O2 -Wall -c create_string.c -o create_string.o

# This will result in:
#
# root@45c98a6c18dc:/# gcc -O2 -Wall -c create_string.c -o create_string.o
# create_string.c: In function ‘create_string’:
# create_string.c:9:3: warning: ‘strncpy’ specified bound depends on the length of the source argument [-Wstringop-overflow=]
#    strncpy(str, value, n);
#    ^~~~~~~~~~~~~~~~~~~~~~
# create_string.c:7:11: note: length computed here
#    int n = strlen(value) + 1;
#            ^~~~~~~~~~~~~


# ====================================================================
#
# To reproduce a WARNING with R CMD check in the sass package, do the following

docker run --rm -ti debian:testing
apt-get update
apt-get install -y gcc vim r-base git

git clone https://github.com/rstudio/sass.git
cd sass
git checkout 6099440
cd ..
R -e "install.packages(c('knitr', 'rmarkdown', 'testthat'))"

# Edit Makeconf. For CFLAGS, add -O2 -Wall, and remove -D_FORTIFY_SOURCE=2
vim /usr/lib/R/etc/Makeconf 

R CMD build --no-build-vignettes sass
R CMD check --no-tests --no-vignettes sass_0.1.1.tar.gz