How is array of string literal in C stored?

Question

Take a look at following code and output:

char *words[] = {"wehrmarcht", "collectorate", "hello", "hello","precorrection", "hello","wehrmarcht"};
char *wp;
cnode *np;
for(wp = *words; wp - *words < sizeof(words); wp += strlen(wp) + 1) {
    printf("wp -> %s\n", wp);
}
printf("==============================================\n");
for(int i = 0; i < sizeof(words) / sizeof(char *); i++) {
    printf("words[%d] -> %s\n", i,words[i]);
}

output:

wp -> collectorate
wp -> precorrection
wp -> wp -> %s

wp -> ==============================================

==============================================
words[0] -> wehrmarcht
words[1] -> collectorate
words[2] -> hello
words[3] -> hello
words[4] -> precorrection
words[5] -> hello
words[6] -> wehrmarcht

Process finished with exit code 0

Can someone explain what makes the wp points to some strings in code? Thanks in advance.

Answer 1

In order to experiment, I just changed your example to display the addresses of the strings.
You can see that we cannot make any assumption about the way each of these strings is stored relative to each other.

On my system (Linux 64-bit) I obtain:

$ ./prog_c
words[0] @ 0x5631c83b6080 -> wehrmarcht
words[1] @ 0x5631c83b60c0 -> collectorate
words[2] @ 0x5631c83b6100 -> hello
words[3] @ 0x5631c83b6100 -> hello
words[4] @ 0x5631c83b6140 -> precorrection
words[5] @ 0x5631c83b6100 -> hello
words[6] @ 0x5631c83b6080 -> wehrmarcht

/**
  gcc -std=c99 -o prog_c prog_c.c \
      -pedantic -Wall -Wextra -Wconversion \
      -Wc++-compat -Wwrite-strings -Wold-style-definition -Wvla \
      -g -O0 -UNDEBUG -fsanitize=address,undefined
**/

#include <stdio.h>

int
main(void)
{
  const char *words[]={"wehrmarcht", "collectorate", "hello", "hello", "precorrection", "hello", "wehrmarcht"};
  const int count=(int)(sizeof(words)/sizeof(words[0]));
  for(int i=0; i<count; ++i)
  {
    printf("words[%d] @ %p -> %s\n", i, (void *)words[i], words[i]);
  }
  return 0;
}