------- Comment #1 from jsm28 at gcc dot gnu dot org 2008-07-01 15:52 ------- I've also observed this problem (as causing a number of GDB testsuite failures).
With both 4.2 and 4.3, the function prologue is followed by a jump, the loop body, and then the test of the loop condition which the jump jumps to. The loop body has the correct line number, as does the condition. With 4.2, the jump has the same line number as the condition, so that's the line number to which GDB assigns a breakpoint on the function. With 4.3, the jump insn does not have a line number and GDB decides to use the line number of the loop body, and the GDB tests fail. -- jsm28 at gcc dot gnu dot org changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Ever Confirmed|0 |1 Last reconfirmed|0000-00-00 00:00:00 |2008-07-01 15:52:34 date| | Summary|.debug_line first line is |[4.3/4.4 Regression] |behind the first instruction|.debug_line first line is | |behind the first instruction Target Milestone|--- |4.3.2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36690