[lld] [ELF] Handle relocations in synthetic .eh_frame with a non-zero offset within the output section (PR #65966)

[via llvm-commits]

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@@ -0,0 +1,55 @@
+// REQUIRES: aarch64
+// RUN: rm -rf %t && split-file %s %t
+
+// RUN: llvm-mc -filetype=obj -triple=aarch64 %t/a.s -o %t/a.o
+// RUN: ld.lld %t/a.o -T %t/eh-frame-non-zero-offset.t -o %t/non-zero
+// RUN: llvm-readelf --program-headers --unwind --symbols -x .eh_frame %t/non-zero | FileCheck --check-prefix=NONZERO %s
+// RUN: ld.lld %t/a.o -T %t/eh-frame-zero-offset.t -o %t/zero
+// RUN: llvm-readelf --program-headers --unwind --symbols -x .eh_frame %t/zero | FileCheck --check-prefix=ZERO %s
+
+// NONZERO:      {{[0-9]+}}: 0000000000000080 {{.*}} __eh_frame_start
+// NONZERO-NEXT: {{[0-9]+}}: 00000000000000ac {{.*}} __eh_frame_end
+
+// NONZERO:      0x00000078 00000000 00000000 10000000 00000000
+// NONZERO-NEXT: 0x00000088 017a5200 017c1e01 1b0c1f00 10000000
+// NONZERO-NEXT: 0x00000098 18000000 64ffffff 08000000 00000000
+// NONZERO-NEXT: 0x000000a8 00000000
+
+// ZERO:      {{[0-9]+}}: 0000000000000080 {{.*}} __eh_frame_start
+// ZERO-NEXT: {{[0-9]+}}: 00000000000000ac {{.*}} __eh_frame_end
+
+// ZERO:      0x00000080 10000000 00000000 017a5200 017c1e01
+// ZERO-NEXT: 0x00000090 1b0c1f00 10000000 18000000 64ffffff
+// ZERO-NEXT: 0x000000a0 08000000 00000000 00000000
+
+//--- eh-frame-non-zero-offset.t
+SECTIONS {
+  .text : { *(.text .text.*) }
+  .eh_frame : {
+  /* Alignment padding within .eh_frame */
+  . = ALIGN(128);
+  __eh_frame_start = .;
+  *(.eh_frame .eh_frame.*) ;
+  __eh_frame_end = .;
+  }
+}
+
+//--- eh-frame-zero-offset.t
+SECTIONS {
+  .text : { *(.text .text.*) }
+  .eh_frame : ALIGN(128) {
+  __eh_frame_start = .;
+  *(.eh_frame .eh_frame.*) ;
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simpal01 wrote:

Done

https://github.com/llvm/llvm-project/pull/65966