https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124651
--- Comment #5 from Heiko Eißfeldt <heiko at hexco dot de> ---
Also I changed function pass_warn_recursion::find_function_exit() as suggested
(i think), but that did not help with the ICE.
Here is my rewrite which searchs until a recursion is found:
```
/* Return true if there is path from BB to M_FUNC exit point along which
there is no (recursive) call to M_FUNC. */
bool
pass_warn_recursion::find_function_exit (basic_block bb_start)
{
// work item list of BB's
auto_vec<basic_block, 1> bbs;
bbs.safe_push(bb_start);
for (const auto &bb : bbs)
{
if (!bitmap_set_bit (m_visited, bb->index))
return false;
if (bb == EXIT_BLOCK_PTR_FOR_FN (m_func))
return true;
/* Iterate over statements in BB, looking for a call to FNDECL. */
for (auto si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next_nondebug
(&si))
{
gimple *stmt = gsi_stmt (si);
if (!is_gimple_call (stmt))
continue;
if (gimple_call_builtin_p (stmt, BUILT_IN_LONGJMP))
/* A longjmp breaks infinite recursion. */
break;
if (tree fndecl = gimple_call_fndecl (stmt))
{
/* A throw statement breaks infinite recursion. */
tree id = DECL_NAME (fndecl);
const char *name = IDENTIFIER_POINTER (id);
if (startswith (name, "__cxa_throw"))
break;
/* As does a call to POSIX siglongjmp. */
if (!strcmp (name, "siglongjmp"))
break;
if (m_built_in
&& gimple_call_builtin_p (stmt, BUILT_IN_NORMAL)
&& m_built_in == DECL_FUNCTION_CODE (fndecl))
{
const char *cname
= IDENTIFIER_POINTER (DECL_NAME (current_function_decl));
/* Don't warn about gnu_inline extern inline function
like strcpy calling __builtin_strcpy, that is fine,
if some call is made (the builtin isn't expanded
inline),
a call is made to the external definition. */
if (!(DECL_DECLARED_INLINE_P (current_function_decl)
&& DECL_EXTERNAL (current_function_decl))
|| strcmp (name, cname) == 0)
{
/* The call is being made from the definition of a
built-in
(e.g., in a replacement of one) to itself. */
m_calls->safe_push (stmt);
return false;
}
}
}
if (noreturn_p)
{
/* A noreturn call breaks infinite recursion. */
int flags = gimple_call_flags (stmt);
if (flags & ECF_NORETURN)
break;
}
tree callee = gimple_call_fndecl (stmt);
if (!callee || m_func->decl != callee)
continue;
/* Add the recursive call to the vector and return false. */
m_calls->safe_push (stmt);
return false;
}
/* If no call to FNDECL has been found search all BB's successors. */
/* Add more BB's to check for on demand. */
edge e;
edge_iterator ei;
FOR_EACH_EDGE (e, ei, bb->succs)
bbs.safe_push (e->dest);
}
return true;
}
```
and the diff
```
diff --git a/gcc/gimple-warn-recursion.cc b/gcc/gimple-warn-recursion.cc
index 67ce192142d..e61548f5c56 100644
--- a/gcc/gimple-warn-recursion.cc
+++ b/gcc/gimple-warn-recursion.cc
@@ -82,83 +82,91 @@ pass_warn_recursion::pass_warn_recursion (gcc::context
*ctxt)
there is no (recursive) call to M_FUNC. */
bool
-pass_warn_recursion::find_function_exit (basic_block bb)
+pass_warn_recursion::find_function_exit (basic_block bb_start)
{
- if (!bitmap_set_bit (m_visited, bb->index))
- return false;
+ // work item list of BB's
+ auto_vec<basic_block, 1> bbs;
+ bbs.safe_push(bb_start);
- if (bb == EXIT_BLOCK_PTR_FOR_FN (m_func))
- return true;
-
- /* Iterate over statements in BB, looking for a call to FNDECL. */
- for (auto si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next_nondebug (&si))
+ for (const auto &bb : bbs)
{
- gimple *stmt = gsi_stmt (si);
- if (!is_gimple_call (stmt))
- continue;
- if (gimple_call_builtin_p (stmt, BUILT_IN_LONGJMP))
- /* A longjmp breaks infinite recursion. */
+ if (!bitmap_set_bit (m_visited, bb->index))
+ return false;
+ if (bb == EXIT_BLOCK_PTR_FOR_FN (m_func))
return true;
- if (tree fndecl = gimple_call_fndecl (stmt))
+ /* Iterate over statements in BB, looking for a call to FNDECL. */
+ for (auto si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next_nondebug
(&si))
{
- /* A throw statement breaks infinite recursion. */
- tree id = DECL_NAME (fndecl);
- const char *name = IDENTIFIER_POINTER (id);
- if (startswith (name, "__cxa_throw"))
- return true;
- /* As does a call to POSIX siglongjmp. */
- if (!strcmp (name, "siglongjmp"))
- return true;
-
- if (m_built_in
- && gimple_call_builtin_p (stmt, BUILT_IN_NORMAL)
- && m_built_in == DECL_FUNCTION_CODE (fndecl))
+ gimple *stmt = gsi_stmt (si);
+ if (!is_gimple_call (stmt))
+ continue;
+
+ if (gimple_call_builtin_p (stmt, BUILT_IN_LONGJMP))
+ /* A longjmp breaks infinite recursion. */
+ break;
+
+ if (tree fndecl = gimple_call_fndecl (stmt))
{
- const char *cname
- = IDENTIFIER_POINTER (DECL_NAME (current_function_decl));
- /* Don't warn about gnu_inline extern inline function
- like strcpy calling __builtin_strcpy, that is fine,
- if some call is made (the builtin isn't expanded inline),
- a call is made to the external definition. */
- if (!(DECL_DECLARED_INLINE_P (current_function_decl)
- && DECL_EXTERNAL (current_function_decl))
- || strcmp (name, cname) == 0)
+ /* A throw statement breaks infinite recursion. */
+ tree id = DECL_NAME (fndecl);
+ const char *name = IDENTIFIER_POINTER (id);
+ if (startswith (name, "__cxa_throw"))
+ break;
+ /* As does a call to POSIX siglongjmp. */
+ if (!strcmp (name, "siglongjmp"))
+ break;
+
+ if (m_built_in
+ && gimple_call_builtin_p (stmt, BUILT_IN_NORMAL)
+ && m_built_in == DECL_FUNCTION_CODE (fndecl))
{
- /* The call is being made from the definition of a built-in
- (e.g., in a replacement of one) to itself. */
- m_calls->safe_push (stmt);
- return false;
+ const char *cname
+ = IDENTIFIER_POINTER (DECL_NAME (current_function_decl));
+ /* Don't warn about gnu_inline extern inline function
+ like strcpy calling __builtin_strcpy, that is fine,
+ if some call is made (the builtin isn't expanded
inline),
+ a call is made to the external definition. */
+ if (!(DECL_DECLARED_INLINE_P (current_function_decl)
+ && DECL_EXTERNAL (current_function_decl))
+ || strcmp (name, cname) == 0)
+ {
+ /* The call is being made from the definition of a
built-in
+ (e.g., in a replacement of one) to itself. */
+ m_calls->safe_push (stmt);
+ return false;
+ }
}
}
- }
- if (noreturn_p)
- {
- /* A noreturn call breaks infinite recursion. */
- int flags = gimple_call_flags (stmt);
- if (flags & ECF_NORETURN)
- return true;
+ if (noreturn_p)
+ {
+ /* A noreturn call breaks infinite recursion. */
+ int flags = gimple_call_flags (stmt);
+ if (flags & ECF_NORETURN)
+ break;
+ }
+
+ tree callee = gimple_call_fndecl (stmt);
+ if (!callee || m_func->decl != callee)
+ continue;
+
+ /* Add the recursive call to the vector and return false. */
+ m_calls->safe_push (stmt);
+ return false;
}
- tree callee = gimple_call_fndecl (stmt);
- if (!callee || m_func->decl != callee)
- continue;
+ /* If no call to FNDECL has been found search all BB's successors. */
+ /* Add more BB's to check for on demand. */
+ edge e;
+ edge_iterator ei;
- /* Add the recursive call to the vector and return false. */
- m_calls->safe_push (stmt);
- return false;
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ bbs.safe_push (e->dest);
}
- /* If no call to FNDECL has been found search all BB's successors. */
- edge e;
- edge_iterator ei;
- FOR_EACH_EDGE (e, ei, bb->succs)
- if (find_function_exit (e->dest))
- return true;
-
- return false;
+ return true;
}
```
