Dueway Qi wrote:
I have found another similar case.
lang_hooks.callgraph.analyze_expr in gcc/gcc/cgraphunit.c
490 if (lang_hooks.callgraph.analyze_expr)
491 return lang_hooks.callgraph.analyze_expr (tp, walk_subtrees,
492 data);
but in another part of this file
517 if ((unsigned int) TREE_CODE (t) >= LAST_AND_UNUSED_TREE_CODE)
518 return lang_hooks.callgraph.analyze_expr (tp,
walk_subtrees, data);
The docs say that analyze_expr is used for unrecognized tree codes. So
if a front end will generate unrecognized tree codes, then it must
define the analyze_expr hook. This explains the second part of this.
If we see an unrecognized tree code, then there is no real need to check
if analyze_expr is defined, because it must be defined. This means
someone writing a language front end would get an ICE here, but an end
user would not. This could be a bit nicer for a language front end
writer, but this doesn't look like a serious problem.
For the first part of this, we don't know for sure if we have any
unrecognized tree codes, so we can't assume that the analyze_expr hook
is defined. We must check first.
This is an analysis from just looking at the code. I haven't tried to
debug it and see what is really going on.
--
Jim Wilson, GNU Tools Support, http://www.specifix.com
