[MC] Rename temporary symbols of empty name to ".L0 " (#89693)
Temporary symbols generated for .eh_frame and .debug_line have an empty
name, which appear in .symtab in the presence of RISC-V style linker
relaxation and will not be discarded by ld/objcopy --discard-locals
(-X).
In contrast, GNU assembler's riscv port assigns a fake name ".L0 " (with
a trailing space) to these symbols so that will be discarded by
ld/objcopy --discard-locals.
This patch matches the GNU behavior. Since Clang's RISC-V targets pass
-X to ld, and GNU ld defaults to -X for RISC-V targets, these ".L0 "
symbols will be discarded after linking by default, as expected by
users.
The llvm-symbolizer special case for RISC-V `SF_FormatSpecific` symbols
https://reviews.llvm.org/D98669 needs to be adjusted.
Note: `"":` in assembly currently crashes.
GitOrigin-RevId: b9f2c16b50f68c978e90190f46a7c0db3f39e98c
diff --git a/test/ELF/mips-eh_frame-pic.s b/test/ELF/mips-eh_frame-pic.s
index a84c36b..c04dbdf 100644
--- a/test/ELF/mips-eh_frame-pic.s
+++ b/test/ELF/mips-eh_frame-pic.s
@@ -36,8 +36,8 @@
# RELOCS: .rel{{a?}}.eh_frame {
# ABS32-RELOCS-NEXT: 0x1C R_MIPS_32 .text
# ABS64-RELOCS-NEXT: 0x1C R_MIPS_64/R_MIPS_NONE/R_MIPS_NONE .text
-# PIC64-RELOCS-NEXT: 0x1C R_MIPS_PC32/R_MIPS_NONE/R_MIPS_NONE <null>
-# PIC32-RELOCS-NEXT: 0x1C R_MIPS_PC32 <null>
+# PIC64-RELOCS-NEXT: 0x1C R_MIPS_PC32/R_MIPS_NONE/R_MIPS_NONE .L0
+# PIC32-RELOCS-NEXT: 0x1C R_MIPS_PC32 .L0
# RELOCS-NEXT: }
# ABS64-EH-FRAME: Augmentation data: 0C
