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| author | Marek Polacek <polacek@redhat.com> | 2023-02-22 15:17:03 -0500 |
|---|---|---|
| committer | Marek Polacek <polacek@redhat.com> | 2023-02-22 17:26:29 -0500 |
| commit | 1370014f2ea02ec185cf1199027575916f79fe63 (patch) | |
| tree | a0f682e9c3913f1dd46f5976721757e55f088891 /gcc/c-family | |
| parent | 31303c9b5bab200754cdb7ef8cd91ae4918f3018 (diff) | |
| download | gcc-1370014f2ea02ec185cf1199027575916f79fe63.zip gcc-1370014f2ea02ec185cf1199027575916f79fe63.tar.gz gcc-1370014f2ea02ec185cf1199027575916f79fe63.tar.bz2 | |
c-family: avoid compile-time-hog in c_genericize [PR108880]
This fixes a compile-time hog with UBSan. This only happened in cc1 but
not cc1plus. The problem is ultimately that c_genericize_control_stmt/
STATEMENT_LIST -> walk_tree_1 doesn't use a hash_set to remember visited
nodes, so it kept on recursing for a long time. We should be able to
use the pset that c_genericize created. We just need to use walk_tree
instead of walk_tree_w_d so that the pset is explicit.
PR c/108880
gcc/c-family/ChangeLog:
* c-gimplify.cc (c_genericize_control_stmt) <case STATEMENT_LIST>: Pass
pset to walk_tree_1.
(c_genericize): Call walk_tree with an explicit pset.
gcc/testsuite/ChangeLog:
* c-c++-common/ubsan/pr108880.c: New test.
Diffstat (limited to 'gcc/c-family')
| -rw-r--r-- | gcc/c-family/c-gimplify.cc | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/gcc/c-family/c-gimplify.cc b/gcc/c-family/c-gimplify.cc index b57546a..74b276b 100644 --- a/gcc/c-family/c-gimplify.cc +++ b/gcc/c-family/c-gimplify.cc @@ -511,12 +511,15 @@ c_genericize_control_stmt (tree *stmt_p, int *walk_subtrees, void *data, STATEMENT_LIST wouldn't be present at all the resulting expression wouldn't have TREE_SIDE_EFFECTS set, so make sure to clear it even on the STATEMENT_LIST in such cases. */ + hash_set<tree> *pset = (c_dialect_cxx () + ? nullptr + : static_cast<hash_set<tree> *>(data)); for (i = tsi_start (stmt); !tsi_end_p (i); tsi_next (&i)) { tree t = tsi_stmt (i); if (TREE_CODE (t) != DEBUG_BEGIN_STMT && nondebug_stmts < 2) nondebug_stmts++; - walk_tree_1 (tsi_stmt_ptr (i), func, data, NULL, lh); + walk_tree_1 (tsi_stmt_ptr (i), func, data, pset, lh); if (TREE_CODE (t) != DEBUG_BEGIN_STMT && (nondebug_stmts > 1 || TREE_SIDE_EFFECTS (tsi_stmt (i)))) clear_side_effects = false; @@ -572,8 +575,9 @@ c_genericize (tree fndecl) bc_state_t save_state; push_cfun (DECL_STRUCT_FUNCTION (fndecl)); save_bc_state (&save_state); - walk_tree_without_duplicates (&DECL_SAVED_TREE (fndecl), - c_genericize_control_r, NULL); + hash_set<tree> pset; + walk_tree (&DECL_SAVED_TREE (fndecl), c_genericize_control_r, &pset, + &pset); restore_bc_state (&save_state); pop_cfun (); } |