bool ARM::needsThunk(RelExpr Expr, RelType Type, const InputFile *File,
uint64_t BranchAddr, const Symbol &S) const {
- // If S is an undefined weak symbol in an executable we don't need a Thunk.
- // In a DSO calls to undefined symbols, including weak ones get PLT entries
- // which may need a thunk.
- if (S.isUndefWeak() && !Config->Shared)
+ // If S is an undefined weak symbol and does not have a PLT entry then it
+ // will be resolved as a branch to the next instruction.
+ if (S.isUndefWeak() && !S.isInPlt())
return false;
// A state change from ARM to Thumb and vice versa must go through an
// interworking thunk if the relocation type is not R_ARM_CALL or
--- /dev/null
+// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %S/Inputs/arm-shared.s -o %t
+// RUN: ld.lld %t --shared -o %t.so
+// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %s -o %t2
+// RUN: ld.lld %t2 %t.so -o %t3
+// RUN: llvm-objdump -d -triple=armv7a-none-linux-gnueabi -start-address=69632 -stop-address=69664 %t3 | FileCheck %s
+// REQUIRES: arm
+
+// When we are dynamic linking, undefined weak references have a PLT entry so
+// we must create a thunk for the branch to the PLT entry.
+
+ .text
+ .globl bar2
+ .weak undefined_weak_we_expect_a_plt_entry_for
+_start:
+ .globl _start
+ .type _start, %function
+ b undefined_weak_we_expect_a_plt_entry_for
+ bl bar2
+// Create 32 Mb gap between the call to the weak reference and the PLT so that
+// the b and bl need a range-extension thunk.
+ .section .text.1, "ax", %progbits
+ .space 32 * 1024 * 1024
+
+// CHECK: Disassembly of section .text:
+// CHECK-NEXT: _start:
+// CHECK-NEXT: 11000: 00 00 00 ea b #0 <__ARMv7ABSLongThunk_undefined_weak_we_expect_a_plt_entry_for>
+// CHECK-NEXT: 11004: 02 00 00 eb bl #8 <__ARMv7ABSLongThunk_bar2>
+// CHECK: __ARMv7ABSLongThunk_undefined_weak_we_expect_a_plt_entry_for:
+// CHECK-NEXT: 11008: 34 c0 01 e3 movw r12, #4148
+// CHECK-NEXT: 1100c: 01 c2 40 e3 movt r12, #513
+// CHECK-NEXT: 11010: 1c ff 2f e1 bx r12
+// CHECK: __ARMv7ABSLongThunk_bar2:
+// CHECK-NEXT: 11014: 44 c0 01 e3 movw r12, #4164
+// CHECK-NEXT: 11018: 01 c2 40 e3 movt r12, #513
+// CHECK-NEXT: 1101c: 1c ff 2f e1 bx r12