[libc-commits] [libc] [libc] fortify jmp buffer for x86-64 (PR #112769)

[Nick Desaulniers via libc-commits]

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@@ -7,59 +7,15 @@
 //===----------------------------------------------------------------------===//
 
 #include "src/setjmp/longjmp.h"
-#include "include/llvm-libc-macros/offsetof-macro.h"
 #include "src/__support/common.h"
 #include "src/__support/macros/config.h"
 
-#if !defined(LIBC_TARGET_ARCH_IS_X86)
-#error "Invalid file include"
+#ifdef LIBC_TARGET_ARCH_IS_X86_64
+#if LIBC_COPT_SETJMP_FORTIFICATION
+#include "longjmp_64_fortified.cpp.inc"
+#else
+#include "longjmp_64.cpp.inc"
 #endif
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nickdesaulniers wrote:

Rather than being done one the preprocessor level, can this be done on the cmake level?  i.e. cmake would look at `LIBC_COPT_SETJMP_FORTIFICATION` and decide whether to build longjmp.cpp vs longjmp_fortified.cpp?

Also, for splitting out i386, you should create an libc/src/setjmp/i386 folder, move the .cpp files there.  Then we just have .cpp files, and no .inc files.

e083a33478b2d570c89d7a9d9f05328b9232c072 made it so that `LIBC_TARGET_ARCHITECTURE` is `"i386"`.  You can test i386 somewhat by setting `-DLIBC_TARGET_TRIPLE=i386-linux-gnu` or `-DLIBC_TARGET_TRIPLE=i386-linux-android` to cmake.

https://github.com/llvm/llvm-project/pull/112769