From af6adb3f5f05be4faa88a5aa83296c388c8085e7 Mon Sep 17 00:00:00 2001
From: "Yann E. MORIN" <yann.morin.1998@free.fr>
Date: Wed, 8 Feb 2023 12:30:10 +0100
Subject: [PATCH] configure: fix build on mips

This patch is a historical baggage that Buildroot has carried for ages
(since 2006), and the reason for it are notentirely clear.

Since dmalloc is pretty tricky, and as this patch has not been
identified as causing issues, we keep it; we just add the configure.ac
patchlet to match the one in configure.

As for the title, the original patch was named dmalloc-mips.patch, so
presumably it fixes some mips issue; let's title the commit that way.

[Fabrice: Updated for 5.6.5]
Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
[yann.morin.1998@free.fr: make it a git-formatted patch]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
---
 configure    |  4 ++--
 configure.ac |  2 +-
 return.h     | 16 +++-------------
 3 files changed, 6 insertions(+), 16 deletions(-)

diff --git a/configure b/configure
index d52a1e8..c18dfb2 100755
--- a/configure
+++ b/configure
@@ -5413,8 +5413,8 @@ fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking return.h macros work" >&5
 $as_echo_n "checking return.h macros work... " >&6; }
 if test "$cross_compiling" = yes; then :
-   $as_echo "#define RETURN_MACROS_WORK 0" >>confdefs.h
- { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+   $as_echo "#define RETURN_MACROS_WORK 1" >>confdefs.h
+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: assume yes (cross-compiling)" >&5
 $as_echo "no" >&6; }
 
 else
diff --git a/configure.ac b/configure.ac
index a5295f1..9740fdc 100644
--- a/configure.ac
+++ b/configure.ac
@@ -705,7 +705,7 @@ int main()
 ])],
 [ AC_DEFINE(RETURN_MACROS_WORK, 1) AC_MSG_RESULT([yes]) ],
 [ AC_DEFINE(RETURN_MACROS_WORK, 0) AC_MSG_RESULT([no]) ],
-[ AC_DEFINE(RETURN_MACROS_WORK, 0) AC_MSG_RESULT([no]) ]
+[ AC_DEFINE(RETURN_MACROS_WORK, 1) AC_MSG_RESULT([assume yes (cross-compiling)]) ]
 )
 
 ##############################################################################
diff --git a/return.h b/return.h
index 9d3f5f1..d916c7a 100644
--- a/return.h
+++ b/return.h
@@ -117,26 +117,16 @@
 /*************************************/
 
 /*
- * For DEC Mips machines running Ultrix
+ * For Mips machines running Linux
  */
 #if __mips
 
-/*
- * I have no idea how to get inline assembly with the default cc.
- * Anyone know how?
- */
-
-#if 0
-
 /*
  * NOTE: we assume here that file is global.
  *
- * $31 is the frame pointer.  $2 looks to be the return address but maybe
- * not consistently.
+ * $31 is the return address.
  */
-#define GET_RET_ADDR(file)	asm("sw $2, file")
-
-#endif
+#define GET_RET_ADDR(file)	asm("sw $31, %0" : "=m" (file))
 
 #endif /* __mips */
 
-- 
2.25.1