diff --git a/gcc/config/riscv/riscv-string.cc b/gcc/config/riscv/riscv-string.cc
index b09b51d7526..41cb061c746 100644
--- a/gcc/config/riscv/riscv-string.cc
+++ b/gcc/config/riscv/riscv-string.cc
@@ -153,7 +153,7 @@ emit_strcmp_scalar_compare_subword (rtx data1, rtx data2, rtx orc1,
   rtx imask = gen_rtx_CONST_INT (Xmode, im);
   rtx m_reg = gen_reg_rtx (Xmode);
   emit_insn (gen_rtx_SET (m_reg, imask));
-  do_rotr3 (m_reg, m_reg, GEN_INT (64 - cmp_bytes * BITS_PER_UNIT));
+  do_rotr3 (m_reg, m_reg, GEN_INT (BITS_PER_WORD - cmp_bytes * BITS_PER_UNIT));
   do_and3 (data1, m_reg, data1);
   do_and3 (data2, m_reg, data2);
   if (TARGET_ZBB)
@@ -497,6 +497,13 @@ riscv_expand_strcmp (rtx result, rtx src1, rtx src2,
 	return false;
       nbytes = UINTVAL (bytes_rtx);
 
+      /* If NBYTES is zero the result of strncmp will always be zero,
+	 but that would require special casing in the caller.  So for
+	 now just don't do an inline expansion.  This probably rarely
+	 happens in practice, but it is tested by the testsuite.  */
+      if (nbytes == 0)
+	return false;
+
       /* We don't emit parts of a strncmp() call.  */
       if (nbytes > compare_max)
 	return false;
diff --git a/gcc/config/riscv/riscv.opt b/gcc/config/riscv/riscv.opt
index 7cca1c4aab2..1252834aec5 100644
--- a/gcc/config/riscv/riscv.opt
+++ b/gcc/config/riscv/riscv.opt
@@ -517,15 +517,15 @@ Target Var(TARGET_INLINE_SUBWORD_ATOMIC) Init(1)
 Always inline subword atomic operations.
 
 minline-strcmp
-Target Var(riscv_inline_strcmp) Init(0)
+Target Var(riscv_inline_strcmp) Init(1)
 Inline strcmp calls if possible.
 
 minline-strncmp
-Target Var(riscv_inline_strncmp) Init(0)
+Target Var(riscv_inline_strncmp) Init(1)
 Inline strncmp calls if possible.
 
 minline-strlen
-Target Var(riscv_inline_strlen) Init(0)
+Target Var(riscv_inline_strlen) Init(1)
 Inline strlen calls if possible.
 
 -param=riscv-strcmp-inline-limit=
diff --git a/gcc/testsuite/gcc.target/riscv/zbb-strlen-disabled-2.c b/gcc/testsuite/gcc.target/riscv/zbb-strlen-disabled-2.c
index a481068aa0c..1295aeb0086 100644
--- a/gcc/testsuite/gcc.target/riscv/zbb-strlen-disabled-2.c
+++ b/gcc/testsuite/gcc.target/riscv/zbb-strlen-disabled-2.c
@@ -1,6 +1,6 @@
 /* { dg-do compile } */
-/* { dg-options "-march=rv32gc_zbb" { target { rv32 } } } */
-/* { dg-options "-march=rv64gc_zbb" { target { rv64 } } } */
+/* { dg-options "-mno-inline-strlen -march=rv32gc_zbb" { target { rv32 } } } */
+/* { dg-options "-mno-inline-strlen -march=rv64gc_zbb" { target { rv64 } } } */
 /* { dg-skip-if "" { *-*-* } { "-O0" "-Os" "-Og" "-Oz" } } */
 
 typedef long unsigned int size_t;