[lld] r368983 - [ELF][AArch64] Improve error message for unknown relocations

[Fangrui Song via llvm-commits]

Author: maskray
Date: Thu Aug 15 03:02:54 2019
New Revision: 368983

URL: http://llvm.org/viewvc/llvm-project?rev=368983&view=rev
Log:
[ELF][AArch64] Improve error message for unknown relocations

Like rLLD354040.

Previously, for unrecognized relocation types, in -no-pie/-pie mode, we got something like:

  foo.o: unrecognized relocation ...

In -shared mode:

  error: can't create dynamic relocation ... against symbol: yyy in readonly segment

Delete the default case from AArch64::getRelExpr and add the error there.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D66277

Added:
    lld/trunk/test/ELF/invalid/invalid-relocation-aarch64.test
Modified:
    lld/trunk/ELF/Arch/AArch64.cpp

Modified: lld/trunk/ELF/Arch/AArch64.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Arch/AArch64.cpp?rev=368983&r1=368982&r2=368983&view=diff
==============================================================================
--- lld/trunk/ELF/Arch/AArch64.cpp (original)
+++ lld/trunk/ELF/Arch/AArch64.cpp Thu Aug 15 03:02:54 2019
@@ -76,6 +76,26 @@ AArch64::AArch64() {
 RelExpr AArch64::getRelExpr(RelType type, const Symbol &s,
                             const uint8_t *loc) const {
   switch (type) {
+  case R_AARCH64_ABS16:
+  case R_AARCH64_ABS32:
+  case R_AARCH64_ABS64:
+  case R_AARCH64_ADD_ABS_LO12_NC:
+  case R_AARCH64_LDST128_ABS_LO12_NC:
+  case R_AARCH64_LDST16_ABS_LO12_NC:
+  case R_AARCH64_LDST32_ABS_LO12_NC:
+  case R_AARCH64_LDST64_ABS_LO12_NC:
+  case R_AARCH64_LDST8_ABS_LO12_NC:
+  case R_AARCH64_MOVW_SABS_G0:
+  case R_AARCH64_MOVW_SABS_G1:
+  case R_AARCH64_MOVW_SABS_G2:
+  case R_AARCH64_MOVW_UABS_G0:
+  case R_AARCH64_MOVW_UABS_G0_NC:
+  case R_AARCH64_MOVW_UABS_G1:
+  case R_AARCH64_MOVW_UABS_G1_NC:
+  case R_AARCH64_MOVW_UABS_G2:
+  case R_AARCH64_MOVW_UABS_G2_NC:
+  case R_AARCH64_MOVW_UABS_G3:
+    return R_ABS;
   case R_AARCH64_TLSDESC_ADR_PAGE21:
     return R_AARCH64_TLSDESC_PAGE;
   case R_AARCH64_TLSDESC_LD64_LO12:
@@ -126,7 +146,9 @@ RelExpr AArch64::getRelExpr(RelType type
   case R_AARCH64_NONE:
     return R_NONE;
   default:
-    return R_ABS;
+    error(getErrorLocation(loc) + "unknown relocation (" + Twine(type) +
+          ") against symbol " + toString(s));
+    return R_NONE;
   }
 }
 
@@ -421,7 +443,7 @@ void AArch64::relocateOne(uint8_t *loc,
     or32AArch64Imm(loc, val);
     break;
   default:
-    error(getErrorLocation(loc) + "unrecognized relocation " + toString(type));
+    llvm_unreachable("unknown relocation");
   }
 }
 

Added: lld/trunk/test/ELF/invalid/invalid-relocation-aarch64.test
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/invalid/invalid-relocation-aarch64.test?rev=368983&view=auto
==============================================================================
--- lld/trunk/test/ELF/invalid/invalid-relocation-aarch64.test (added)
+++ lld/trunk/test/ELF/invalid/invalid-relocation-aarch64.test Thu Aug 15 03:02:54 2019
@@ -0,0 +1,31 @@
+# REQUIRES: aarch64
+# RUN: yaml2obj %s -o %t.o
+# RUN: not ld.lld %t.o -o /dev/null 2>&1 | FileCheck %s
+# CHECK: error: unknown relocation (1024) against symbol foo
+# CHECK: error: unknown relocation (1025) against symbol foo
+
+!ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_REL
+  Machine:         EM_AARCH64
+Sections:
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC ]
+  - Name:            .rela.text
+    Type:            SHT_RELA
+    Link:            .symtab
+    Info:            .text
+    Relocations:
+      - Offset:          0x0000000000000000
+        Symbol:          foo
+        Type:            0x400
+      - Offset:          0x0000000000000000
+        Symbol:          foo
+        Type:            0x401
+Symbols:
+  - Name:            foo
+    Section:         .text
+    Binding:         STB_GLOBAL