template <class ELFT> void Writer<ELFT>::writeHeader() {
uint8_t *Buf = Buffer->getBufferStart();
+ // For executable segments, the trap instructions are written before writing
+ // the header. Setting Elf header bytes to zero ensures that any unused bytes
+ // in header are zero-cleared, instead of having trap instructions.
+ memset(Buf, 0, sizeof(Elf_Ehdr));
memcpy(Buf, "\177ELF", 4);
// Write the ELF header.
--- /dev/null
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
+# RUN: ld.lld %t.o -o %t1
+# RUN: llvm-readobj -file-headers %t1 | FileCheck %s
+
+# RUN: ld.lld %t.o -no-rosegment -o %t2
+# RUN: llvm-readobj -file-headers %t2 | FileCheck %s
+
+# CHECK: ElfHeader {
+# CHECK-NEXT: Ident {
+# CHECK-NEXT: Magic: (7F 45 4C 46)
+# CHECK-NEXT: Class: 64-bit (0x2)
+# CHECK-NEXT: DataEncoding: LittleEndian (0x1)
+# CHECK-NEXT: FileVersion: 1
+# CHECK-NEXT: OS/ABI: SystemV (0x0)
+# CHECK-NEXT: ABIVersion: 0
+# CHECK-NEXT: Unused: (00 00 00 00 00 00 00)
+# CHECK-NEXT: }