Handle R_ARM_TARGET1 as a synonym for R_ARM_ABS32

This fixes a regression introduced in 431fc39.

Fixes #1351

Author: rui314

src/output-chunks.cc

@@ -1109,11 +1109,21 @@ template <typename E>
 void OutputSection<E>::scan_abs_relocations(Context<E> &ctx) {
   std::vector<std::vector<AbsRel<E>>> shards(members.size());
 
+  auto is_absrel = [](const ElfRel<E> &r) {
+    // R_ARM_TARGET1 is typically used for entries in .init_array and can
+    // be interpreted as REL32 or ABS32 depending on the target.
+    // All targets we support handle it as if it were a synonym for ABS32.
+    if constexpr (is_arm32<E>)
+      if (r.r_type == R_ARM_TARGET1)
+        return true;
+    return r.r_type == E::R_ABS;
+  };
+
   // Collect all word-size absolute relocations
   tbb::parallel_for((i64)0, (i64)members.size(), [&](i64 i) {
     InputSection<E> *isec = members[i];
     for (const ElfRel<E> &r : isec->get_rels(ctx))
-      if (r.r_type == E::R_ABS)
+      if (is_absrel(r))
         shards[i].push_back(AbsRel<E>{isec, r.r_offset, isec->file.symbols[r.r_sym],
                                       get_addend(*isec, r)});
   });

test/arch-arm-target1.sh

@@ -0,0 +1,19 @@
+#!/bin/bash
+. $(dirname $0)/common.inc
+
+cat <<EOF | $CC -c -o $t/a.o -xassembler -
+.globl foo
+.data
+foo:
+.word bar(TARGET1)
+EOF
+
+cat <<EOF | $CC -fPIC -c -o $t/b.o -xc -
+#include <stdio.h>
+extern char *foo;
+char bar[] = "Hello world";
+int main() { printf("%s\n", foo); }
+EOF
+
+$CC -B. -o $t/exe -pie $t/a.o $t/b.o
+$QEMU $t/exe | grep -q 'Hello world'