[ELF][CHERI] Delete an obsolete check

This dates back to 2021; such object files are long past their support
window.

Author: jrtc27

lld/ELF/Arch/Cheri.cpp

@@ -905,16 +905,6 @@ void addCapabilityRelocation(
     RelocationBaseSection *dynRelSec) {
   Symbol *sym = dyn_cast<Symbol *>(symOrSec);
   assert(expr == R_CHERI_CAPABILITY);
-  if (sec->name == ".gcc_except_table" && sym && sym->isPreemptible) {
-    // We previously had an ugly workaround here to create a hidden alias for
-    // relocations in the exception table, but this has since been fixed in
-    // the compiler. Add an explicit error here in case someone tries to
-    // link against object files/static libraries from an old toolchain.
-    auto diag = ctx.arg.noinhibitExec ? Warn(ctx) : Err(ctx);
-    diag << "got relocation against preemptible symbol " << toStr(ctx, *sym)
-         << " in exception handling table. Please recompile this file!\n"
-         << ">>> referenced by " << sec->getObjMsg(offset);
-  }
 
   bool needTrampoline = false;
   // In the PLT ABI (and fndesc?) we have to use an elf relocation for function

lld/test/ELF/cheri/function-with-offset-reloc.s

@@ -0,0 +1,25 @@
+# REQUIRES: riscv
+# RUN: %riscv64_cheri_purecap_llvm-mc -filetype=obj %s -o %t.o
+# RUN: ld.lld -shared %t.o -o %t.so 2>&1 | FileCheck --implicit-check-not=warning: %s
+
+  .type local, @function
+local:
+  cret
+  .size local, . - local
+
+  .type global, @function
+  .global global
+global:
+  cret
+  .size global, . - global
+
+  .type undef, @function
+  .global undef
+
+  .data
+foo:
+  .chericap local + 1
+  # CHECK: warning: got capability relocation with non-zero addend (0x1) against function global. This may not be supported by the runtime linker.
+  .chericap global + 1
+  # CHECK: warning: got capability relocation with non-zero addend (0x1) against function undef. This may not be supported by the runtime linker.
+  .chericap undef + 1