| From: Mark Wielaard <mark@klomp.org> |
| Date: Thu, 26 Jan 2023 17:19:15 +0000 (+0100) |
| Subject: backends: Handle DW_TAG_unspecified_type in dwarf_peeled_die_type |
| X-Git-Url: https://sourceware.org/git/?p=elfutils.git;a=commitdiff_plain;h=f2c522567ad63ac293535fba9704895e685ab5bc;hp=3fa98a6f29b0f370e32549ead7eb897c839af980 |
| |
| backends: Handle DW_TAG_unspecified_type in dwarf_peeled_die_type |
| |
| binutils 2.40 introduces DW_TAG_unspecified_type for assembly |
| functions with an unknown return type. This breaks the |
| run-funcretval.sh testcase because dwfl_module_return_value_location |
| returns an error for such functions because it cannot determine the |
| return value location. Fix that by treating DW_TAG_unspecified_type |
| as if the DIE doesn't have a DW_AT_type. |
| |
| Also update the testcase to explicitly checking for |
| DW_TAG_unspecified_type and printing "returns unspecified type". |
| |
| https://sourceware.org/bugzilla/show_bug.cgi?id=30047 |
| |
| Upstream-Status: Backport [https://sourceware.org/git/?p=elfutils.git;a=commitdiff;h=f2c522567ad63ac293535fba9704895e685ab5bc;hp=3fa98a6f29b0f370e32549ead7eb897c839af980] |
| Signed-off-by: Mark Wielaard <mark@klomp.org> |
| --- |
| |
| --- a/backends/libebl_CPU.h |
| +++ b/backends/libebl_CPU.h |
| @@ -1,5 +1,6 @@ |
| /* Common interface for libebl modules. |
| Copyright (C) 2000, 2001, 2002, 2003, 2005, 2013, 2014 Red Hat, Inc. |
| + Copyright (C) 2023 Mark J. Wielaard <mark@klomp.org> |
| This file is part of elfutils. |
| |
| This file is free software; you can redistribute it and/or modify |
| @@ -53,7 +54,9 @@ extern bool (*generic_debugscn_p) (const |
| dwarf_tag (_die); }) |
| |
| /* Get a type die corresponding to DIE. Peel CV qualifiers off |
| - it. */ |
| + it. Returns zero if the DIE doesn't have a type, or the type |
| + is DW_TAG_unspecified_type. Returns -1 on error. Otherwise |
| + returns the result tag DW_AT value. */ |
| static inline int |
| dwarf_peeled_die_type (Dwarf_Die *die, Dwarf_Die *result) |
| { |
| @@ -69,7 +72,14 @@ dwarf_peeled_die_type (Dwarf_Die *die, D |
| if (dwarf_peel_type (result, result) != 0) |
| return -1; |
| |
| - return DWARF_TAG_OR_RETURN (result); |
| + if (result == NULL) |
| + return -1; |
| + |
| + int tag = dwarf_tag (result); |
| + if (tag == DW_TAG_unspecified_type) |
| + return 0; /* Treat an unspecified type as if there was no type. */ |
| + |
| + return tag; |
| } |
| |
| #endif /* libebl_CPU.h */ |
| --- a/tests/funcretval.c |
| +++ b/tests/funcretval.c |
| @@ -1,5 +1,6 @@ |
| /* Test program for dwfl_module_return_value_location. |
| Copyright (C) 2005 Red Hat, Inc. |
| + Copyright (C) 2023 Mark J. Wielaard <mark@klomp.org> |
| This file is part of elfutils. |
| |
| This file is free software; you can redistribute it and/or modify |
| @@ -67,7 +68,18 @@ handle_function (Dwarf_Die *funcdie, voi |
| error (EXIT_FAILURE, 0, "dwfl_module_return_value_location: %s", |
| dwfl_errmsg (-1)); |
| else if (nlocops == 0) |
| - puts ("returns no value"); |
| + { |
| + // Check if this is the special unspecified type |
| + // https://sourceware.org/bugzilla/show_bug.cgi?id=30047 |
| + Dwarf_Die die_mem, *typedie = &die_mem; |
| + Dwarf_Attribute attr_mem, *attr; |
| + attr = dwarf_attr_integrate (funcdie, DW_AT_type, &attr_mem); |
| + if (dwarf_formref_die (attr, typedie) != NULL |
| + && dwarf_tag (typedie) == DW_TAG_unspecified_type) |
| + puts ("returns unspecified type"); |
| + else |
| + puts ("returns no value"); |
| + } |
| else |
| { |
| printf ("return value location:"); |