[ELF] Change default output section type to SHT_PROGBITS

This fixes an issue where a symbol only section at the start of a PT_LOAD segment, causes incorrect alignment of the file offset for the start of the segment which results in the output of an invalid ELF. SHT_PROGBITS was the default output section type in the past. Differential Revision: https://reviews.llvm.org/D60131 llvm-svn: 358981
llvm · Apr 23, 2019 · ccba42c · ccba42c
1 parent 2769d58
commit ccba42c
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Showing 7 changed files with 45 additions and 10 deletions.
diff --git a/lld/ELF/LinkerScript.cpp b/lld/ELF/LinkerScript.cpp
@@ -86,7 +86,7 @@ OutputSection *LinkerScript::createOutputSection(StringRef Name,
     // There was a forward reference.
     Sec = SecRef;
   } else {
-    Sec = make<OutputSection>(Name, SHT_NOBITS, 0);
+    Sec = make<OutputSection>(Name, SHT_PROGBITS, 0);
     if (!SecRef)
       SecRef = Sec;
   }

diff --git a/lld/test/ELF/linkerscript/arm-exidx-order.test b/lld/test/ELF/linkerscript/arm-exidx-order.test
@@ -13,7 +13,7 @@ SECTIONS {
 # CHECK:      Section {
 # CHECK:        Index:
 # CHECK:        Name: .foo
-# CHECK-NEXT:   Type: SHT_NOBITS
+# CHECK-NEXT:   Type: SHT_PROGBITS
 # CHECK-NEXT:   Flags [
 # CHECK-NEXT:     SHF_ALLOC
 # CHECK-NEXT:   ]
diff --git a/lld/test/ELF/linkerscript/extend-pt-load2.test b/lld/test/ELF/linkerscript/extend-pt-load2.test
@@ -17,8 +17,8 @@ SECTIONS {
 }
 
 # CHECK:      .text        PROGBITS 00000000000001bc 0001bc 000001 00 AX
-# CHECK-NEXT: bar          NOBITS   00000000000001bd 0001bd 000e43 00 AX
+# CHECK-NEXT: bar          PROGBITS 00000000000001bd 0001bd 000e43 00 AX
 # CHECK-NEXT: .data.rel.ro PROGBITS 0000000000001000 001000 000001 00 WA
 
-# CHECK:      LOAD 0x000000 0x0000000000000000 0x0000000000000000 0x0001bd 0x001000 R E
+# CHECK:      LOAD 0x000000 0x0000000000000000 0x0000000000000000 0x001000 0x001000 R E
 # CHECK-NEXT: LOAD 0x001000 0x0000000000001000 0x0000000000001000 0x000068 0x000068 RW
diff --git a/lld/test/ELF/linkerscript/merge-sections.s b/lld/test/ELF/linkerscript/merge-sections.s
@@ -35,7 +35,7 @@
 # RUN: llvm-readobj -s -t %t2 | FileCheck %s --check-prefix=GC
 
 # GC:        Name: .foo
-# GC-NEXT:   Type: SHT_NOBITS
+# GC-NEXT:   Type: SHT_PROGBITS
 # GC-NEXT:   Flags [
 # GC-NEXT:     SHF_ALLOC
 # GC-NEXT:   ]

diff --git a/lld/test/ELF/linkerscript/orphan-phdrs.s b/lld/test/ELF/linkerscript/orphan-phdrs.s
@@ -23,13 +23,13 @@
 
 # CHECK: Segment Sections
 # CHECK-NEXT: .text .orphan
-# CHECK-NEXT: .rw
+# CHECK-NEXT: .empty .rw
 
-.section .text, "ax"
+.section .text,"ax"
  ret
 
-.section .rw, "aw"
+.section .rw,"aw"
  .quad 0
 
-.section .orphan, "ax"
+.section .orphan,"ax"
  ret
diff --git a/lld/test/ELF/linkerscript/symbol-only-align.test b/lld/test/ELF/linkerscript/symbol-only-align.test
@@ -0,0 +1,35 @@
+# REQUIRES: x86
+# RUN: echo '.text; ret; .data; .quad 0' > %t.s
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %t.s -o %t.o
+# RUN: ld.lld -o %t --script %s %t.o -shared
+# RUN: llvm-readobj -elf-output-style=GNU -s -t -l %t | FileCheck %s
+
+PHDRS {
+  text PT_LOAD FLAGS(0x5);
+  data PT_LOAD FLAGS(0x6);
+}
+
+SECTIONS {
+  . = SIZEOF_HEADERS;
+  .text : { *(.text) } : text
+  . = ALIGN(CONSTANT(MAXPAGESIZE));
+  foo : { __start_foo = .; *(foo); __end_foo = .; } : data
+  .data : { *(.data) }
+  .dynamic : { *(.dynamic) }
+}
+
+## Check that foo, the symbol only section, has the expected aligned address and
+## file offset. Also check that the section's symbols and the data segment's
+## offset and addresses match.
+
+# CHECK: Section Headers
+# CHECK:      foo   PROGBITS 0000000000[[ADDR:[0-9a-f]*]] [[ADDR]]
+# CHECK-NEXT: .data PROGBITS 0000000000[[ADDR]] [[ADDR]]
+
+# CHECK: Symbol table
+# CHECK: 0000000000[[ADDR]] 0 NOTYPE GLOBAL DEFAULT {{[0-9]+}} __start_foo
+# CHECK: 0000000000[[ADDR]] 0 NOTYPE GLOBAL DEFAULT {{[0-9]+}} __end_foo
+
+# CHECK: Program Headers
+# CHECK:      LOAD
+# CHECK-NEXT: LOAD 0x[[ADDR]] 0x0000000000[[ADDR]] 0x0000000000[[ADDR]]
diff --git a/lld/test/ELF/linkerscript/symbol-only-flags.test b/lld/test/ELF/linkerscript/symbol-only-flags.test
@@ -14,7 +14,7 @@ SECTIONS {
 # CHECK:     Section {
 # CHECK:       Index:
 # CHECK:       Name: .foo
-# CHECK-NEXT:  Type: SHT_NOBITS
+# CHECK-NEXT:  Type: SHT_PROGBITS
 # CHECK-NEXT:  Flags [
 # CHECK-NEXT:    SHF_ALLOC
 # CHECK-NEXT:    SHF_WRITE