Bug#1086830: ghc FTBFS on alpha with gcc 14

[Adrian Bunk]

Source: ghc
Version: 9.6.6-2
Severity: important
Tags: ftbfs patch
Forwarded: https://github.com/ghc/ghc/commit/5099057b7eaa08d53c8ab07be0f6d626496ec79d
X-Debbugs-Cc: John Paul Adrian Glaubitz <glaubitz at physik.fu-berlin.de>

https://buildd.debian.org/status/fetch.php?pkg=ghc&arch=alpha&ver=9.6.6-1~exp4&stamp=1724733137&raw=0

...
===> Command failed with error code: 1
rts/posix/Signals.c: In function ‘initDefaultHandlers’:

rts/posix/Signals.c:709:5: error:
     error: implicit declaration of function ‘ieee_set_fp_control’ [-Wimplicit-function-declaration]
      709 |     ieee_set_fp_control(0);
          |     ^~~~~~~~~~~~~~~~~~~
    |
709 |     ieee_set_fp_control(0);
    |     ^
...


The upstreamed fix is also attached.
-------------- next part --------------
From 5099057b7eaa08d53c8ab07be0f6d626496ec79d Mon Sep 17 00:00:00 2001
From: John Paul Adrian Glaubitz <glaubitz at physik.fu-berlin.de>
Date: Thu, 3 Oct 2024 14:30:23 +0200
Subject: rts: Fix invocation of __ieee_set_fp_control() on alpha-linux
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Fixes the following error when building GHC on alpha-linux:

rts/posix/Signals.c: In function ‘initDefaultHandlers’:

rts/posix/Signals.c:709:5: error:
     error: implicit declaration of function ‘ieee_set_fp_control’ [-Wimplicit-function-declaration]
      709 |     ieee_set_fp_control(0);
          |     ^~~~~~~~~~~~~~~~~~~
    |
709 |     ieee_set_fp_control(0);
    |
---
 rts/posix/Signals.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/rts/posix/Signals.c b/rts/posix/Signals.c
index b6bfe77f35..7c788b82b2 100644
--- a/rts/posix/Signals.c
+++ b/rts/posix/Signals.c
@@ -27,7 +27,7 @@
 
 #if defined(alpha_HOST_ARCH)
 # if defined(linux_HOST_OS)
-#  include <asm/fpu.h>
+#  include <fenv.h>
 # else
 #  include <machine/fpu.h>
 # endif
@@ -721,7 +721,11 @@ initDefaultHandlers(void)
 #endif
 
 #if defined(alpha_HOST_ARCH)
+# if defined(linux_HOST_OS)
+    __ieee_set_fp_control(0);
+# else
     ieee_set_fp_control(0);
+# endif
 #endif
 
     // ignore SIGPIPE; see #1619
-- 
2.30.2