Add a testcase for PR binutils/27202

PR binutils/27202
	* testsuite/gas/elf/dwarf-5-loc0.d: New file.
	* testsuite/gas/elf/dwarf-5-loc0.s: Likewise.
	* testsuite/gas/elf/elf.exp: Run dwarf-5-loc0.

gas/testsuite/gas/elf/dwarf-5-loc0.d

@@ -0,0 +1,16 @@
+#as: -gdwarf-5
+#readelf: -wL
+#name: DWARF5 .loc 0
+# The am33 cr16 crx ft32 mn10 msp430 nds32 and rl78 targets do not evaluate the subtraction of symbols at assembly time.
+# The riscv targets do not support the subtraction of symbols.
+#xfail: am3*-* cr16-* crx-* ft32*-* mn10*-* msp430-* nds32*-* riscv*-* rl78-*
+
+Contents of the \.debug_line section:
+
+CU: \./foo\.c:
+File name +Line number +Starting address +View +Stmt
+
+\./foo.c:\[\+\+\]
+foo\.c +1 +0x8 +x
+foo\.c +2 +0x10 +x
+foo\.c +- +0x10

gas/testsuite/gas/elf/dwarf-5-loc0.s

@@ -0,0 +1,11 @@
+	.file "foo.c"
+	.text
+	.balign 16
+	.globl _start
+_start:
+	.file 0 "foo.c"
+	.quad 0
+	.loc 0 1 view 0
+	.balign 16
+	.loc 0 2 view 0
+	.size _start, .-_start

gas/testsuite/gas/elf/elf.exp

@@ -300,6 +300,7 @@ if { [is_elf_format] } then {
     run_dump_test "dwarf-5-file0" $dump_opts
     run_dump_test "dwarf-5-file0-2" $dump_opts
     run_dump_test "dwarf-5-dir0" $dump_opts
+    run_dump_test "dwarf-5-loc0" $dump_opts
     run_dump_test "dwarf-4-cu" $dump_opts
     run_dump_test "dwarf-5-cu" $dump_opts
     run_dump_test "dwarf-5-nop-for-line-table" $dump_opts