[patch] Fix PR lto/50492
Fri Oct 7 11:14:00 GMT 2011
this is another LTO bootstrap failure with Ada enabled. There are 2 problems:
1. dwarf2out.c thinks that it is processing pure C++ code for gnat1 so it is
invoking some C++-specific code paths that aren't compatible with Ada. Fixed
by building TRANSLATION_UNIT_DECL nodes in Ada as well.
2. the recent change:
* gimple.c (canonicalize_cond_expr_cond): Handle cast from
breaks cross-language inlining. More specifically, it removes a necessary cast
between an Ada boolean type and a C boolean type (hence a GIMPLE verification
failure later) when __gnat_is_absolute_path is inlined into Is_Absolute_Path:
extern int __gnat_is_absolute_path (char *, int);
function Is_Absolute_Path (Name : String) return Boolean is
(Name : Address;
Length : Integer) return Integer;
pragma Import (C, Is_Absolute_Path, "__gnat_is_absolute_path");
return Is_Absolute_Path (Name'Address, Name'Length) /= 0;
We start with:
Ada_Boolean_Var = (Integer_Var != 0);
and forwprop figures out that (Integer_Var != 0) is equivalent to iftmp.xxx.
In combine_cond_expr_cond, the constant folder correctly turns this into:
Ada_Boolean_Var = (Ada_Boolean_Type) iftmp.xxx;
but the call to canonicalize_cond_expr_cond wrongly removes the cast.
Note that changing Ada's boolean_type_node to a C-compatible type doesn't fix
the problem as the boolean return type of Is_Absolute_Path has to be an Ada
boolean type in any case, so a cast will be always necessary here.
Since reverting the canonicalize_cond_expr_cond change apparently has no effect
(no regressions detected on x86 and x86-64), the proposed fix is just that.
Bootstrapped/regtested on x86_64-suse-linux, OK for mainline?
2011-10-07 Eric Botcazou <email@example.com>
* gimple.c (canonicalize_cond_expr_cond): Revert 2011-08-02 change.
* gcc-interface/gigi.h (gnat_pushdecl): Adjust comment.
* gcc-interface/utils.c (global_context): New variable.
(gnat_pushdecl): Initialize it and set it as the DECL_CONTEXT of DECLs
that are either public external or at top level. Use "No" macro.
(end_subprog_body): Call decl_function_context.
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