[lld][ELF] Mark empty NOLOAD output sections SHT_NOBITS instead of SHT_PROGBITS

This fixes PR# 45336.
Output sections described in a linker script as NOLOAD with no input sections would be marked as SHT_PROGBITS.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D76981

Author: schultetwin1

lld/ELF/ScriptParser.cpp

@@ -746,6 +746,7 @@ bool ScriptParser::readSectionDirective(OutputSection *cmd, StringRef tok1, Stri
   expect("(");
   if (consume("NOLOAD")) {
     cmd->noload = true;
+    cmd->type = SHT_NOBITS;
   } else {
     skip(); // This is "COPY", "INFO" or "OVERLAY".
     cmd->nonAlloc = true;

lld/test/ELF/linkerscript/noload.s

@@ -3,13 +3,15 @@
 # RUN: echo "SECTIONS { \
 # RUN:        .data_noload_a (NOLOAD) : { *(.data_noload_a) } \
 # RUN:        .data_noload_b (0x10000) (NOLOAD) : { *(.data_noload_b) } \
+# RUN:        .no_input_sec_noload (NOLOAD) : { . += 1; } \
 # RUN:        .text (0x20000) : { *(.text) } };" > %t.script
 # RUN: ld.lld -o %t --script %t.script %t.o
 # RUN: llvm-readelf -S -l %t | FileCheck %s
 
-# CHECK:      Name           Type   Address          Off               Size
-# CHECK:      .data_noload_a NOBITS 0000000000000000 [[OFF:[0-9a-f]+]] 001000
-# CHECK-NEXT: .data_noload_b NOBITS 0000000000010000 [[OFF]]           001000
+# CHECK:      Name                 Type   Address          Off               Size
+# CHECK:      .data_noload_a       NOBITS 0000000000000000 [[OFF:[0-9a-f]+]] 001000
+# CHECK-NEXT: .data_noload_b       NOBITS 0000000000010000 [[OFF]]           001000
+# CHECK-NEXT: .no_input_sec_noload NOBITS 0000000000011000 [[OFF]]           000001
 
 # CHECK:      Type Offset   VirtAddr           PhysAddr
 # CHECK-NEXT: LOAD 0x001000 0x0000000000020000 0x0000000000020000