gdb/testsuite/gdb.base/lineinc.c

   1 /* The following is written to tickle a specific bug in the macro
   2    table code (now hopefully fixed), which doesn't insert new included
   3    files in the #including file's list in the proper place.  They
   4    should be sorted by the number of the line which #included them, in
   5    increasing order, but the sense of the comparison was reversed, so
   6    the list ends up being built backwards.  This isn't a problem by
   7    itself, but the code to pick new, non-conflicting line numbers for
   8    headers alleged to be #included at the same line as some other
   9    header assumes that the list's line numbers are in ascending order.
  10
  11    So, given the following input, lineinc1.h gets added to lineinc.c's
  12    #inclusion list first, at line 10.  When the debug info reader
  13    tries to add lineinc2.h at line 10 as well, the code will notice the
  14    duplication --- since there's only one extant element in the list,
  15    it'll find it --- and insert it after lineinc1.h, with line 11.
  16    Since the code is putting the list in order of descending
  17    #inclusion line number, the list is now out of order.  When we try
  18    to #include lineinc3.h at line 11, we won't notice the duplication.  */
  19
  20 #line 10
  21 #include "lineinc1.h"
  22 #line 10
  23 #include "lineinc2.h"
  24 #line 11
  25 #include "lineinc3.h"
  26
  27 int
  28 main (int argc, char **argv)
  29 {
  30 }