Bizzarre GCC/Unixlib problem

As part of developing a program in C to process an error listing and generate appropriate error messages, I encountered what seems to be a bug in Unixlib (GCC 4.1.2, RO 5.19, Raspberry Pi).

Given the following test file contents:

lout file "test-err":
    16,1: symbol @GP unknown or misspelt

and the following code to process it:

int main(int argc, char** argv)
{
   FILE *f;                /* input file */
   char buffer[132];       /* buffer to read line into */
   int line;               /* line number */

   f=fopen(argv[1],"r");

   fgets(buffer,132,f);

   printf("Entering while loop\n");

   while (!feof(f)) {
     line=atoi(buffer);

     printf("%d : %s\n",line,buffer);
     fgets(buffer,132,f);
   }
}

it works as intended when compiled under gcc with -mlibscl (or under Norcroft, for that matter) but results in an endless loop if a Unixlib program is produced with gcc, whether dynamic or static.

If you’re interested, you can find a .zip file containing all three versions of the program (called testdynamic, teststatic and testscl) together with the relevant data file here

Same result here using GCC 4.1.2 on Iyonix.

if (fgets(buffer,132,f)==NULL)
      return 0;