2009-03-04 Richard Guenther PR tree-optimization/39358 * tree-ssa-structalias.c (do_sd_constraint): Fix check for escaped_id and callused_id. (solve_graph): Likewise. * g++.dg/warn/Wstrict-aliasing-bogus-escape-2.C: New testcase. * g++.dg/warn/Wstrict-aliasing-bogus-escape-3.C: Likewise. --- gcc/tree-ssa-structalias.c (revision 144601) +++ gcc/tree-ssa-structalias.c (revision 144602) @@ -1524,8 +1524,8 @@ do_sd_constraint (constraint_graph_t gra of a variable can also reach all other fields of the variable we simply have to expand the solution to contain all sub-fields if one sub-field is contained. */ - if (c->rhs.var == escaped_id - || c->rhs.var == callused_id) + if (c->rhs.var == find (escaped_id) + || c->rhs.var == find (callused_id)) { bitmap vars = NULL; /* In a first pass record all variables we need to add all @@ -1594,9 +1594,10 @@ do_sd_constraint (constraint_graph_t gra /* Merging the solution from ESCAPED needlessly increases the set. Use ESCAPED as representative instead. Same for CALLUSED. */ - else if (get_varinfo (t)->id == escaped_id - || get_varinfo (t)->id == callused_id) - flag |= bitmap_set_bit (sol, get_varinfo (t)->id); + else if (get_varinfo (t)->id == find (escaped_id)) + flag |= bitmap_set_bit (sol, escaped_id); + else if (get_varinfo (t)->id == find (callused_id)) + flag |= bitmap_set_bit (sol, callused_id); else if (add_graph_edge (graph, lhs, t)) flag |= bitmap_ior_into (sol, get_varinfo (t)->solution); } @@ -2516,8 +2517,8 @@ solve_graph (constraint_graph_t graph) if (!solution_empty /* Do not propagate the ESCAPED/CALLUSED solutions. */ - && i != escaped_id - && i != callused_id) + && i != find (escaped_id) + && i != find (callused_id)) { bitmap_iterator bi; --- gcc/testsuite/g++.dg/warn/Wstrict-aliasing-bogus-escape-2.C (revision 0) +++ gcc/testsuite/g++.dg/warn/Wstrict-aliasing-bogus-escape-2.C (revision 144602) @@ -0,0 +1,19 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -Wstrict-aliasing" } */ + +#include + +struct A +{ + virtual ~A(); +}; + +A* foo(); + +void bar(std::list x) +{ + std::list y = x; + if (*y.rbegin()) + delete foo(); +} + --- gcc/testsuite/g++.dg/warn/Wstrict-aliasing-bogus-escape-3.C (revision 0) +++ gcc/testsuite/g++.dg/warn/Wstrict-aliasing-bogus-escape-3.C (revision 144602) @@ -0,0 +1,35 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -Wstrict-aliasing" } */ + +struct Node_base {}; + +struct Node : Node_base +{ + int data; +}; + +struct List +{ + Node_base node, *prev; + + List() : prev(&node) { xyz(); } + + void xyz(); + + int back() { return static_cast(prev)->data; } +}; + +struct A +{ + virtual ~A(); +}; + +A* foo(); + +void bar() +{ + List y; + if (y.back()) + delete foo(); +} +