We were calling get_page() with t2 index which is not correct, since get_page() operate on t1 indices. The bug is here from day-1, from 60f781c4 (first version of bounds checker) and show as a crash in __bound_delete_region() at program exit: $ ./tcc -B. -DTCC_TARGET_I386 -DCONFIG_MULTIARCHDIR=\"i386-linux-gnu\" -b -run -DONE_SOURCE \ ./tcc.c -B. -DTCC_TARGET_I386 -DCONFIG_MULTIARCHDIR=\"i386-linux-gnu\" -run -DONE_SOURCE \ ./tcc.c -B. -run tests/tcctest.c (lot's of correct output from tcctest) Runtime error: dereferencing invalid pointer at 0xa7c21cc4 __bound_delete_region() by (nil) ??? Segmentation fault The fix is simple - last page should be get through t1_end, like it is done in __bound_new_region(). After this patch, tcc is being able to compile itself with -b, then compile itself again and run tcctest with correct output. Tests follow.
Unified · Split
| @@ -613,7 +613,7 @@ int __bound_delete_region(void *p) · 612 unmodified lines | |||
| 613 | } | 613 | } |
| 614 | } | 614 | } |
| 615 | /* last page */ | 615 | /* last page */ |
| 616 | page = get_page(t2_end); | 616 | page = get_page(t1_end); |
| 617 | e2 = (BoundEntry *)((char *)page + t2_end); | 617 | e2 = (BoundEntry *)((char *)page + t2_end); |
| 618 | for(e=page;e<e2;e++) { | 618 | for(e=page;e<e2;e++) { |
| 619 | e->start = 0; | 619 | e->start = 0; |