diff --git a/lld/ELF/Arch/RISCV.cpp b/lld/ELF/Arch/RISCV.cpp
--- a/lld/ELF/Arch/RISCV.cpp
+++ b/lld/ELF/Arch/RISCV.cpp
@@ -108,7 +108,10 @@
 }
 
 uint32_t RISCV::calcEFlags() const {
-  assert(!objectFiles.empty());
+  // If there are only binary input files (from -b binary), use a
+  // value of 0 for the ELF header flags.
+  if (objectFiles.empty())
+    return 0;
 
   uint32_t target = getEFlags(objectFiles.front());
 
diff --git a/lld/test/ELF/riscv-elf-flags.s b/lld/test/ELF/riscv-elf-flags.s
new file mode 100644
--- /dev/null
+++ b/lld/test/ELF/riscv-elf-flags.s
@@ -0,0 +1,8 @@
+# REQUIRES: riscv
+
+# RUN: echo -n "BLOB" > %t.binary
+# RUN: ld.lld -m elf64lriscv -b binary %t.binary -o %t.out
+# RUN: llvm-readobj -h %t.out | FileCheck %s
+
+# CHECK:      Flags [
+# CHECK-NEXT: ]