| Andrew Geissler | 6aa7eec | 2023-03-03 12:41:14 -0600 | [diff] [blame^] | 1 | From: Mark Wielaard <mark@klomp.org> |
| 2 | Date: Thu, 26 Jan 2023 17:19:15 +0000 (+0100) |
| 3 | Subject: backends: Handle DW_TAG_unspecified_type in dwarf_peeled_die_type |
| 4 | X-Git-Url: https://sourceware.org/git/?p=elfutils.git;a=commitdiff_plain;h=f2c522567ad63ac293535fba9704895e685ab5bc;hp=3fa98a6f29b0f370e32549ead7eb897c839af980 |
| 5 | |
| 6 | backends: Handle DW_TAG_unspecified_type in dwarf_peeled_die_type |
| 7 | |
| 8 | binutils 2.40 introduces DW_TAG_unspecified_type for assembly |
| 9 | functions with an unknown return type. This breaks the |
| 10 | run-funcretval.sh testcase because dwfl_module_return_value_location |
| 11 | returns an error for such functions because it cannot determine the |
| 12 | return value location. Fix that by treating DW_TAG_unspecified_type |
| 13 | as if the DIE doesn't have a DW_AT_type. |
| 14 | |
| 15 | Also update the testcase to explicitly checking for |
| 16 | DW_TAG_unspecified_type and printing "returns unspecified type". |
| 17 | |
| 18 | https://sourceware.org/bugzilla/show_bug.cgi?id=30047 |
| 19 | |
| 20 | Upstream-Status: Backport [https://sourceware.org/git/?p=elfutils.git;a=commitdiff;h=f2c522567ad63ac293535fba9704895e685ab5bc;hp=3fa98a6f29b0f370e32549ead7eb897c839af980] |
| 21 | Signed-off-by: Mark Wielaard <mark@klomp.org> |
| 22 | --- |
| 23 | |
| 24 | --- a/backends/libebl_CPU.h |
| 25 | +++ b/backends/libebl_CPU.h |
| 26 | @@ -1,5 +1,6 @@ |
| 27 | /* Common interface for libebl modules. |
| 28 | Copyright (C) 2000, 2001, 2002, 2003, 2005, 2013, 2014 Red Hat, Inc. |
| 29 | + Copyright (C) 2023 Mark J. Wielaard <mark@klomp.org> |
| 30 | This file is part of elfutils. |
| 31 | |
| 32 | This file is free software; you can redistribute it and/or modify |
| 33 | @@ -53,7 +54,9 @@ extern bool (*generic_debugscn_p) (const |
| 34 | dwarf_tag (_die); }) |
| 35 | |
| 36 | /* Get a type die corresponding to DIE. Peel CV qualifiers off |
| 37 | - it. */ |
| 38 | + it. Returns zero if the DIE doesn't have a type, or the type |
| 39 | + is DW_TAG_unspecified_type. Returns -1 on error. Otherwise |
| 40 | + returns the result tag DW_AT value. */ |
| 41 | static inline int |
| 42 | dwarf_peeled_die_type (Dwarf_Die *die, Dwarf_Die *result) |
| 43 | { |
| 44 | @@ -69,7 +72,14 @@ dwarf_peeled_die_type (Dwarf_Die *die, D |
| 45 | if (dwarf_peel_type (result, result) != 0) |
| 46 | return -1; |
| 47 | |
| 48 | - return DWARF_TAG_OR_RETURN (result); |
| 49 | + if (result == NULL) |
| 50 | + return -1; |
| 51 | + |
| 52 | + int tag = dwarf_tag (result); |
| 53 | + if (tag == DW_TAG_unspecified_type) |
| 54 | + return 0; /* Treat an unspecified type as if there was no type. */ |
| 55 | + |
| 56 | + return tag; |
| 57 | } |
| 58 | |
| 59 | #endif /* libebl_CPU.h */ |
| 60 | --- a/tests/funcretval.c |
| 61 | +++ b/tests/funcretval.c |
| 62 | @@ -1,5 +1,6 @@ |
| 63 | /* Test program for dwfl_module_return_value_location. |
| 64 | Copyright (C) 2005 Red Hat, Inc. |
| 65 | + Copyright (C) 2023 Mark J. Wielaard <mark@klomp.org> |
| 66 | This file is part of elfutils. |
| 67 | |
| 68 | This file is free software; you can redistribute it and/or modify |
| 69 | @@ -67,7 +68,18 @@ handle_function (Dwarf_Die *funcdie, voi |
| 70 | error (EXIT_FAILURE, 0, "dwfl_module_return_value_location: %s", |
| 71 | dwfl_errmsg (-1)); |
| 72 | else if (nlocops == 0) |
| 73 | - puts ("returns no value"); |
| 74 | + { |
| 75 | + // Check if this is the special unspecified type |
| 76 | + // https://sourceware.org/bugzilla/show_bug.cgi?id=30047 |
| 77 | + Dwarf_Die die_mem, *typedie = &die_mem; |
| 78 | + Dwarf_Attribute attr_mem, *attr; |
| 79 | + attr = dwarf_attr_integrate (funcdie, DW_AT_type, &attr_mem); |
| 80 | + if (dwarf_formref_die (attr, typedie) != NULL |
| 81 | + && dwarf_tag (typedie) == DW_TAG_unspecified_type) |
| 82 | + puts ("returns unspecified type"); |
| 83 | + else |
| 84 | + puts ("returns no value"); |
| 85 | + } |
| 86 | else |
| 87 | { |
| 88 | printf ("return value location:"); |