Re: [PATCH] AArch64: Prioritise init_have_lse_atomics constructor [PR 105708]

[Wilco Dijkstra <Wilco.Dijkstra@arm.com>]

Hi Richard,

I've added a comment - as usual it's just a number. A quick grep in gcc and
glibc showed that priorities 98-101 are used, so I just went a bit below so it
has a higher priority than typical initializations.

Cheers,
Wilco

Here is v2:

Increase the priority of the init_have_lse_atomics constructor so it runs
before other constructors. This improves chances that rr works when LSE
atomics are supported.

Regress and bootstrap pass, OK for commit?

2022-05-24  Wilco Dijkstra  <wdijkstr@arm.com>

libgcc/
        PR libgcc/105708
        * config/aarch64/lse-init.c: Increase constructor priority.

---

diff --git a/libgcc/config/aarch64/lse-init.c b/libgcc/config/aarch64/lse-init.c
index fc875b7fe80e947623e570eac130e7a14b516551..33b97c8d766895cf0101a851e1dc4ed6a1a053d9 100644
--- a/libgcc/config/aarch64/lse-init.c
+++ b/libgcc/config/aarch64/lse-init.c
@@ -38,7 +38,9 @@ _Bool __aarch64_have_lse_atomics
 
 unsigned long int __getauxval (unsigned long int);
 
-static void __attribute__((constructor))
+/* Use a higher priority to ensure it runs before user constructors
+   and library constructors with priority 100. */
+static void __attribute__((constructor (90)))
 init_have_lse_atomics (void)
 {
   unsigned long hwcap = __getauxval (AT_HWCAP);