From 04e28fdda03b545a0f7b446a784ec2fa7249cbb8 Mon Sep 17 00:00:00 2001
From: Khem Raj <raj.khem@gmail.com>
Date: Wed, 29 Apr 2020 15:37:40 -0700
Subject: [PATCH] Fix build on riscv32

Define __NR_mmap in terms of __NR_mmap2 and __NR_futex interms of
__NR_futex_time64 for rv32, since there calls dont exist for rv32

Also recognise rv32 as a new 32bit platform

Upstream-Status: Submitted [https://github.com/abseil/abseil-cpp/pull/675]
Signed-off-by: Khem Raj <raj.khem@gmail.com>
---
 absl/base/internal/direct_mmap.h        | 5 +++++
 absl/base/internal/spinlock_linux.inc   | 4 ++++
 absl/synchronization/internal/waiter.cc | 4 ++++
 3 files changed, 13 insertions(+)

diff --git a/absl/base/internal/direct_mmap.h b/absl/base/internal/direct_mmap.h
index 5618867..90cfeca 100644
--- a/absl/base/internal/direct_mmap.h
+++ b/absl/base/internal/direct_mmap.h
@@ -26,6 +26,10 @@
 
 #ifdef __linux__
 
+#if !defined(__NR_mmap) && defined(__riscv) && __riscv_xlen == 32
+# define __NR_mmap __NR_mmap2
+#endif
+
 #include <sys/types.h>
 #ifdef __BIONIC__
 #include <sys/syscall.h>
@@ -72,6 +76,7 @@ inline void* DirectMmap(void* start, size_t length, int prot, int flags, int fd,
 #if defined(__i386__) || defined(__ARM_ARCH_3__) || defined(__ARM_EABI__) || \
     (defined(__mips__) && _MIPS_SIM == _MIPS_SIM_ABI32) ||                   \
     (defined(__PPC__) && !defined(__PPC64__)) ||                             \
+    (defined(__riscv) && __riscv_xlen == 32)  ||                             \
     (defined(__s390__) && !defined(__s390x__))
   // On these architectures, implement mmap with mmap2.
   static int pagesize = 0;
diff --git a/absl/base/internal/spinlock_linux.inc b/absl/base/internal/spinlock_linux.inc
index 323edd6..3dca444 100644
--- a/absl/base/internal/spinlock_linux.inc
+++ b/absl/base/internal/spinlock_linux.inc
@@ -14,6 +14,10 @@
 //
 // This file is a Linux-specific part of spinlock_wait.cc
 
+#if !defined(__NR_futex) && defined(__riscv) && __riscv_xlen == 32
+# define __NR_futex __NR_futex_time64
+#endif
+
 #include <linux/futex.h>
 #include <sys/syscall.h>
 #include <unistd.h>
diff --git a/absl/synchronization/internal/waiter.cc b/absl/synchronization/internal/waiter.cc
index 2949f5a..7411042 100644
--- a/absl/synchronization/internal/waiter.cc
+++ b/absl/synchronization/internal/waiter.cc
@@ -24,6 +24,10 @@
 #include <unistd.h>
 #endif
 
+#if !defined(__NR_futex) && defined(__riscv) && __riscv_xlen == 32
+# define __NR_futex __NR_futex_time64
+#endif
+
 #ifdef __linux__
 #include <linux/futex.h>
 #include <sys/syscall.h>
-- 
2.26.2