Hi Liming, > -----Original Message----- > From: Gao, Liming > Sent: Wednesday, June 5, 2019 1:57 PM > To: devel@edk2.groups.io; Lu, XiaoyuX <xiaoyux...@intel.com> > Cc: Bi, Dandan <dandan...@intel.com>; Wang, Jian J <jian.j.w...@intel.com> > Subject: RE: [edk2-devel] [PATCH v1 1/1] CryptoPkg/IntrinsicLib: Fix > CLANG38 IA32 build problem > > Xiaoyu: > > >-----Original Message----- > >From: devel@edk2.groups.io [mailto:devel@edk2.groups.io] On Behalf Of > >Xiaoyu Lu > >Sent: Wednesday, June 05, 2019 1:25 PM > >To: devel@edk2.groups.io > >Cc: Lu, XiaoyuX <xiaoyux...@intel.com>; Bi, Dandan > <dandan...@intel.com>; > >Wang, Jian J <jian.j.w...@intel.com> > >Subject: [edk2-devel] [PATCH v1 1/1] CryptoPkg/IntrinsicLib: Fix CLANG38 > >IA32 build problem > > > >When use clang-3.8 to build the NetworkPkg, compiler optimization > >may use memcpy for memory copy. For example: > > > > CryptoPkg/Library/OpensslLib/openssl/ssl/ssl_rsa.c:918: undefined > > reference to `memcpy'` > > > >Compiler optimization is sophisticated, but we can work around it > >use __attribute__((__used__)) to informs the compiler that symbol > >should be retained in the object file, even if it may be > >unreferenced. > > > >Cc: Jian J Wang <jian.j.w...@intel.com> > >Cc: Dandan Bi <dandan...@intel.com> > >Signed-off-by: Xiaoyu Lu <xiaoyux...@intel.com> > >--- > > CryptoPkg/Library/IntrinsicLib/CopyMem.c | 13 +++++++++++++ > > 1 file changed, 13 insertions(+) > > > >diff --git a/CryptoPkg/Library/IntrinsicLib/CopyMem.c > >b/CryptoPkg/Library/IntrinsicLib/CopyMem.c > >index e29b4918d200..7faf5a34d8c1 100644 > >--- a/CryptoPkg/Library/IntrinsicLib/CopyMem.c > >+++ b/CryptoPkg/Library/IntrinsicLib/CopyMem.c > >@@ -10,8 +10,21 @@ SPDX-License-Identifier: BSD-2-Clause-Patent > > #include <Base.h> > > #include <Library/BaseMemoryLib.h> > > > >+#if defined(__clang__) && !defined(__APPLE__) > > So, this change is only for CLANG tool chain. > > >+ > >+/* Copies bytes between buffers */ > >+static __attribute__((__used__)) > > What purpose for static? >
Because I want __memcpy only use in this file scope. > >+void * __memcpy (void *dest, const void *src, unsigned int count) > >+{ > >+ return CopyMem (dest, src, (UINTN)count); > >+} > >+__attribute__((__alias__("__memcpy"))) > >+void * memcpy (void *dest, const void *src, unsigned int count); > > __memcpy is IA32 Intrinsic API, memcpy is X64 Intrinsic API, right? > __memcpy isn't IA32 Intrinsic API, only memcpy is intrinsic API for both IA32 and X64. The reason I alias memcpy and use __attribute__((__used__)) is let compiler retain symbol in object file, So it can link correct. Is this correct? > Thanks > Liming > >+ > >+#else > > /* Copies bytes between buffers */ > > void * memcpy (void *dest, const void *src, unsigned int count) > > { > > return CopyMem (dest, src, (UINTN)count); > > } > >+#endif > >-- > >2.7.4 > > > > > > -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#41914): https://edk2.groups.io/g/devel/message/41914 Mute This Topic: https://groups.io/mt/31934411/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-