| Summary: | [3.4/4.0 Regression] verify_local_live_at_start ICE after crossjumping & cfgcleanup | ||
|---|---|---|---|
| Product: | gcc | Reporter: | Richard Sandiford <rsandifo> |
| Component: | rtl-optimization | Assignee: | Richard Sandiford <rsandifo> |
| Status: | RESOLVED FIXED | ||
| Severity: | critical | CC: | gcc-bugs |
| Priority: | P2 | Keywords: | ice-on-valid-code |
| Version: | 3.4.1 | ||
| Target Milestone: | 3.4.2 | ||
| Host: | Target: | mips64-elf | |
| Build: | Known to work: | 3.3.3 | |
| Known to fail: | Last reconfirmed: | ||
Compiling: void f (int a, int b, int c, int d, int e, int *f) { if (a == 0) if (b == 0) if (c == 0) if (d == 0) { *f += e; return; } *f += e; return; } with "mips64-elf-gcc -O2" gives: /tmp/foo.c: In function `f': /tmp/foo.c:13: internal compiler error: in verify_local_live_at_start, at flow.c:546 Please submit a full bug report, with preprocessed source if appropriate. See <URL:http://gcc.gnu.org/bugs.html> for instructions. Same thing for other mips targets, like mips64-linux-gnu. The problem is really target-independent: cleanup_cfg (CLEANUP_CFGLAYOUT), called from within bbreorder, is deleting uses of registers and not updating liveness information. This in turn seems to expose a problem with try_simplify_condjump() not updating the forwarder block flags. Testing a couple of fixes now.