From 917bdf821db4b7610a6cb0d70d0d09a1fc345602 Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Wed, 28 Oct 2009 18:37:11 +0000 Subject: [PATCH] * dwarf2-frame.c (dwarf2_build_frame_info): Discard --gc-section leftover FDEs. --- gdb/ChangeLog | 5 +++++ gdb/dwarf2-frame.c | 44 +++++++++++++++++++++++++++++++------------- 2 files changed, 36 insertions(+), 13 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index c080900..a58386d 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,10 @@ 2009-10-28 Pedro Alves + * dwarf2-frame.c (dwarf2_build_frame_info): Discard --gc-section + leftover FDEs. + +2009-10-28 Pedro Alves + * infrun.c (keep_going): Wrap with resume_cleanups. 2009-10-27 Paul Pluzhnikov diff --git a/gdb/dwarf2-frame.c b/gdb/dwarf2-frame.c index 5e9be2c..51e0dd4 100644 --- a/gdb/dwarf2-frame.c +++ b/gdb/dwarf2-frame.c @@ -2101,7 +2101,8 @@ dwarf2_build_frame_info (struct objfile *objfile) if (fde_table.num_entries != 0) { struct dwarf2_fde_table *fde_table2; - int i, j; + struct dwarf2_fde *fde_prev = NULL; + int i; /* Prepare FDE table for lookups. */ qsort (fde_table.entries, fde_table.num_entries, @@ -2110,22 +2111,39 @@ dwarf2_build_frame_info (struct objfile *objfile) /* Copy fde_table to obstack: it is needed at runtime. */ fde_table2 = (struct dwarf2_fde_table *) obstack_alloc (&objfile->objfile_obstack, sizeof (*fde_table2)); + fde_table2->num_entries = 0; /* Since we'll be doing bsearch, squeeze out identical (except for eh_frame_p) fde entries so bsearch result is predictable. */ - for (i = 0, j = 0; j < fde_table.num_entries; ++i) - { - const int k = j; - - obstack_grow (&objfile->objfile_obstack, &fde_table.entries[j], - sizeof (fde_table.entries[0])); - while (++j < fde_table.num_entries - && (fde_table.entries[k]->initial_location - == fde_table.entries[j]->initial_location)) - /* Skip. */; - } + for (i = 0; i < fde_table.num_entries; i++) + { + struct dwarf2_fde *fde = fde_table.entries[i]; + + /* Check for leftovers from --gc-sections. The GNU linker + sets the relevant symbols to zero, but doesn't zero the + FDE *end* ranges because there's no relocation there. + It's (offset, length), not (start, end). On targets + where address zero is just another valid address this can + be a problem, since the FDEs appear to be non-empty in + the output --- we could pick out the wrong FDE. To work + around this, when overlaps are detected, we prefer FDEs + that do not start at zero. */ + if (fde->initial_location == 0 + && (i + 1) < fde_table.num_entries + && ((fde_table.entries[i + 1])->initial_location + < fde->initial_location + fde->address_range)) + continue; + + if (fde_prev != NULL + && fde_prev->initial_location == fde->initial_location) + continue; + + obstack_grow (&objfile->objfile_obstack, &fde_table.entries[i], + sizeof (fde_table.entries[0])); + ++fde_table2->num_entries; + fde_prev = fde; + } fde_table2->entries = obstack_finish (&objfile->objfile_obstack); - fde_table2->num_entries = i; set_objfile_data (objfile, dwarf2_frame_objfile_data, fde_table2); /* Discard the original fde_table. */ -- 2.7.4