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| author | David Malcolm <dmalcolm@redhat.com> | 2020-02-26 09:43:57 -0500 |
|---|---|---|
| committer | David Malcolm <dmalcolm@redhat.com> | 2020-02-26 21:02:53 -0500 |
| commit | 0ba70d1b5ae8df6406a880b2d23e4710b393e8c9 (patch) | |
| tree | 52b4c8b2498c56cabb21025e9283280cf37870ae /gcc/analyzer | |
| parent | 89f759ac2ebb9f09ce5655ce5d791793922c612d (diff) | |
| download | gcc-0ba70d1b5ae8df6406a880b2d23e4710b393e8c9.zip gcc-0ba70d1b5ae8df6406a880b2d23e4710b393e8c9.tar.gz gcc-0ba70d1b5ae8df6406a880b2d23e4710b393e8c9.tar.bz2 | |
analyzer: fix ICE on unreachable calls [PR 93947]
PR analyzer/93947 reports an ICE at -O1 when attempting to analyze a
call that has been optimized away as unreachable.
The root cause is a NULL dereference due to the fndecl having a NULL
cgraph_node: the cgraph_node was created by
pass_build_cgraph_edges::execute, but was later removed by
symbol_table::remove_unreachable_nodes before the analyzer pass.
This patch fixes it by checking for NULL before handling the
cgraph_node.
The reproducer demonstrates a weakness in the analyzer's constraint
handling, where region_model::apply_constraints_for_gswitch fails
to spot when the cases fully cover the data type, and thus make the
default impossible. For now this is xfail-ed in the testcase.
gcc/analyzer/ChangeLog:
PR analyzer/93947
* region-model.cc (region_model::get_fndecl_for_call): Gracefully
fail for fn_decls that don't have a cgraph_node.
gcc/testsuite/ChangeLog:
PR analyzer/93947
* gcc.dg/analyzer/torture/pr93947.c: New test.
Diffstat (limited to 'gcc/analyzer')
| -rw-r--r-- | gcc/analyzer/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/analyzer/region-model.cc | 6 |
2 files changed, 10 insertions, 2 deletions
diff --git a/gcc/analyzer/ChangeLog b/gcc/analyzer/ChangeLog index 982cc3c..92377be 100644 --- a/gcc/analyzer/ChangeLog +++ b/gcc/analyzer/ChangeLog @@ -1,5 +1,11 @@ 2020-02-26 David Malcolm <dmalcolm@redhat.com> + PR analyzer/93947 + * region-model.cc (region_model::get_fndecl_for_call): Gracefully + fail for fn_decls that don't have a cgraph_node. + +2020-02-26 David Malcolm <dmalcolm@redhat.com> + * bar-chart.cc: New file. * bar-chart.h: New file. * engine.cc: Include "analyzer/bar-chart.h". diff --git a/gcc/analyzer/region-model.cc b/gcc/analyzer/region-model.cc index a71884d..b2179bd 100644 --- a/gcc/analyzer/region-model.cc +++ b/gcc/analyzer/region-model.cc @@ -6732,8 +6732,10 @@ region_model::get_fndecl_for_call (const gcall *call, tree fn_decl = code->get_tree_for_child_region (fn_rid); if (!fn_decl) return NULL_TREE; - const cgraph_node *ultimate_node - = cgraph_node::get (fn_decl)->ultimate_alias_target (); + cgraph_node *node = cgraph_node::get (fn_decl); + if (!node) + return NULL_TREE; + const cgraph_node *ultimate_node = node->ultimate_alias_target (); if (ultimate_node) return ultimate_node->decl; } |