In change #146863 we moved definitions of preinit/init/fini arrays to header but unintentionally moved outside of the namespace. Since the namespace also controls the visibility (through LIBC_NAMESPACE_DECL), as a consequence these symbols no longer have the hidden visibility which changes the codegen from: ``` 4: 4c11 ldr r4, [pc, #0x44] @ 0x4c <__libc_init_array+0x4c> 6: 4812 ldr r0, [pc, #0x48] @ 0x50 <__libc_init_array+0x50> 8: 447c add r4, pc a: 4478 add r0, pc c: 1b00 subs r0, r0, r4 ``` to: ``` 4: 4813 ldr r0, [pc, #0x4c] @ 0x54 <__libc_init_array+0x54> 6: 4914 ldr r1, [pc, #0x50] @ 0x58 <__libc_init_array+0x58> 8: 4478 add r0, pc a: 4479 add r1, pc c: 6804 ldr r4, [r0] e: 6808 ldr r0, [r1] 10: 1b00 subs r0, r0, r4 ``` The `ldr` will trigger a fault in case where these symbols aren't pointing to a valid memory location which is sometimes the case when the array is empty.
25 lines
808 B
C++
25 lines
808 B
C++
//===-- Implementation header of __libc_init_array ------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#include "hdr/stdint_proxy.h"
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#include "src/__support/macros/config.h"
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// NOTE: The namespace is necessary here to set the correct symbol visibility.
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namespace LIBC_NAMESPACE_DECL {
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extern "C" {
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extern uintptr_t __preinit_array_start[];
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extern uintptr_t __preinit_array_end[];
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extern uintptr_t __init_array_start[];
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extern uintptr_t __init_array_end[];
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void __libc_init_array(void);
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} // extern "C"
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} // namespace LIBC_NAMESPACE_DECL
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