gdb/testsuite/gdb.dwarf2/shortpiece.exp

# Copyright 2017-2026 Free Software Foundation, Inc.

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

load_lib dwarf.exp

# This test can only be run on targets which support DWARF-2 and use gas.
require dwarf2_support

standard_testfile main.c -dw.S

# Make some DWARF for the test.
set asm_file [standard_output_file $srcfile2]
Dwarf::assemble $asm_file {
    global pair

    cu { addr_size 4 } {
	compile_unit {} {
	    declare_labels int_label ushort_label struct_label struct_label_2

	    int_label: DW_TAG_base_type {
		DW_AT_byte_size 4 DW_FORM_udata
		DW_AT_encoding @DW_ATE_unsigned
		DW_AT_name "myint"
	    }
	    ushort_label: DW_TAG_base_type {
		DW_AT_byte_size 2 DW_FORM_udata
		DW_AT_encoding @DW_ATE_unsigned
		DW_AT_name "myushort"
	    }

	    struct_label: DW_TAG_structure_type {
		DW_AT_name "S"
		DW_AT_byte_size 8 DW_FORM_udata
	    } {
		DW_TAG_member {
		    DW_AT_name "a"
		    DW_AT_type :${int_label}
		    DW_AT_data_member_location 0 DW_FORM_udata
		}

		DW_TAG_member {
		    DW_AT_name "b"
		    DW_AT_type :${ushort_label}
		    DW_AT_data_member_location 4 DW_FORM_udata
		}
	    }

	    struct_label_2: DW_TAG_structure_type {
		DW_AT_name "S_2"
		DW_AT_byte_size 6 DW_FORM_udata
	    } {
		DW_TAG_member {
		    DW_AT_name "a"
		    DW_AT_type :${int_label}
		    DW_AT_data_member_location 0 DW_FORM_udata
		}

		DW_TAG_member {
		    DW_AT_name "b"
		    DW_AT_type :${ushort_label}
		    DW_AT_data_member_location 4 DW_FORM_udata
		}
	    }

	    DW_TAG_variable {
		DW_AT_name "s1"
		DW_AT_type :${struct_label}
		DW_AT_external 1 DW_FORM_flag
		DW_AT_location {
		    DW_OP_constu 1
		    DW_OP_stack_value
		    DW_OP_piece 4
		    DW_OP_constu 0
		    DW_OP_stack_value
		    DW_OP_piece 2
		} SPECIAL_expr
	    }

	    DW_TAG_variable {
		DW_AT_name "s2"
		DW_AT_type :${struct_label}
		DW_AT_external 1 DW_FORM_flag
		DW_AT_location {
		    DW_OP_constu 1
		    DW_OP_stack_value
		    DW_OP_piece 4
		    DW_OP_constu 0
		    DW_OP_stack_value
		    DW_OP_piece 8
		} SPECIAL_expr
	    }

	    DW_TAG_variable {
		DW_AT_name "s3"
		DW_AT_type :${struct_label_2}
		DW_AT_external 1 DW_FORM_flag
		DW_AT_location {
		    DW_OP_constu 0
		    DW_OP_stack_value
		    DW_OP_piece 4
		    DW_OP_constu 1
		    DW_OP_stack_value
		    DW_OP_piece 2
		} SPECIAL_expr
	    }
	}
    }
}

if { [prepare_for_testing "failed to prepare" ${testfile} \
			  [list $srcfile $asm_file] {nodebug}] } {
    return
}

gdb_test "p s1" " = {a = 1, b = 0}"
gdb_test "p s2" \
    "access outside bounds of object referenced via synthetic pointer"

# When fetching a lazy value, GDB typically tries to fetch the 'full'
# object based on the enclosing type.  GDB does not support the reading
# of a pieced value with a (possibly larger) enclosing type.  However,
# the user may want to print a value casted to a different type,
# e.g. print (<type> []) <variable>.  This cast causes an update of the
# value's type.  In case of a pieced value, GDB failed to fetch the
# value's content.
# This test verifies that GDB can print a pieced value casted to a
# different type.
gdb_test "p (int \[\]) s1" " = \\{1, <optimized out>\\}"
set re_little [string_to_regexp "{1, 0, 0, <optimized out>}"]
set re_big  [string_to_regexp "{0, 1, 0, <optimized out>}"]
gdb_test {p (short []) s1} " = ($re_little|$re_big)"

# Test for correct output if the size of the original object is not a
# multiple of the array's element size.
gdb_test "p s3" " = {a = 0, b = 1}"
gdb_test {p (int []) s3} \
    [multi_line \
	 "warning: array element type size does not divide object size in cast" \
	 [quotemeta "$@DECIMAL = {0}"]]