From: Michael Jeanson <mjeanson@efficios.com>
Date: Mon, 22 Jul 2024 17:47:33 +0000 (-0400)
Subject: Allow building with GCC >= 13.3 on RISC-V
X-Git-Tag: v0.14.1~2
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=86cca1f6d1a6052817ed671255b022f04a22226f;p=userspace-rcu.git

Allow building with GCC >= 13.3 on RISC-V

Building with GCC was marked as broken on RISC-V in
"46980605309e922d14f646c6705d184cb674c0f7". The patches fixing the issue
with atomic operations were included in the GCC 14 branch and backported
to 13.3.0.

Add the appropriate checks to allow building on RISC-V with the fixed
GCC versions.

Tested with GCC 13.3.0 on a VisionFive 2 board.

Change-Id: I9e4498640116b2b5fe73dd8e1822309444130998
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/include/urcu/uatomic/riscv.h b/include/urcu/uatomic/riscv.h
index 1bf82d6..5bd1f80 100644
--- a/include/urcu/uatomic/riscv.h
+++ b/include/urcu/uatomic/riscv.h
@@ -31,15 +31,18 @@
 /*
  * See <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104831> for details.
  *
- * Until the following patches are backported, Userspace RCU is broken for the
- * RISC-V architecture when compiled with GCC.
+ * The following GCC patches are required to have a working Userspace RCU on
+ * the RISC-V architecture. The were introduced in GCC 14 and backported to
+ * 13.3.0.
  *
- *  - <https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=4990cf84c460f064d6281d0813f20b0ef20c7448>
+ *  - <https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=dcd7b2f5f7233a04c8b14b362d0befa76e9654c0>
  *  - <https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=4990cf84c460f064d6281d0813f20b0ef20c7448>
  *  - <https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d199d2e56da2379004e7e0457150409c0c99d3e6>
  */
 #ifdef URCU_GCC_VERSION
-# error "Implementations of some atomic operations of GCC for RISC-V are insufficient for sequential consistency. For this reason Userspace RCU is currently marked as 'broken' for RISC-V with GCC. However, it is still possible to use other toolchains."
+# if (URCU_GCC_VERSION < 130300)
+#  error "Implementations of some atomic operations of GCC < 13.3.0 for RISC-V are insufficient for sequential consistency. For this reason Userspace RCU is currently marked as 'broken' for RISC-V on these GCC versions."
+# endif
 #endif
 
 #ifdef __cplusplus