Copied from Debian.

From: Dave Martin
Subject: "rsc" doesnt exist anymore in thumb2

diff --git a/fixed.h b/fixed.h
index 4b58abf..ba4bc26 100644
--- a/fixed.h
+++ b/fixed.h
@@ -275,12 +275,25 @@ mad_fixed_t mad_f_mul_inline(mad_fixed_t x, mad_fixed_t y)
 	 : "+r" (lo), "+r" (hi)  \
 	 : "%r" (x), "r" (y))
 
+#ifdef __thumb__
+/* In Thumb-2, the RSB-immediate instruction is only allowed with a zero
+	operand.  If needed this code can also support Thumb-1 
+	(simply append "s" to the end of the second two instructions). */
+#  define MAD_F_MLN(hi, lo)  \
+    asm ("rsbs        %0, %0, #0\n\t"  \
+	 "sbc   %1, %1, %1\n\t"  \
+	 "sub   %1, %1, %2"  \
+	 : "+&r" (lo), "=&r" (hi)  \
+	 : "r" (hi)  \
+	 : "cc")
+#else /* ! __thumb__ */
 #  define MAD_F_MLN(hi, lo)  \
     asm ("rsbs	%0, %2, #0\n\t"  \
 	 "rsc	%1, %3, #0"  \
-	 : "=r" (lo), "=r" (hi)  \
+	 : "=&r" (lo), "=r" (hi)  \
 	 : "0" (lo), "1" (hi)  \
 	 : "cc")
+#endif /* __thumb__ */
 
 #  define mad_f_scale64(hi, lo)  \
     ({ mad_fixed_t __result;  \
>
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<tr><td><span title='2024-04-23 16:45:34 +0800'>2024-04-23</span></td><td><a href='/guix/commit/gnu/packages/debug.scm?id=2d19e505f6f9f82aebc9ba8c74ba223818acd9bc'>gnu: Add cppdap.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/debug.scm (cppdap): New variable.
* gnu/packages/patches/cppdap-add-CPPDAP_USE_EXTERNAL_GTEST_PACKAGE.patch: New
patch.
* gnu/local.mk (dist_patch_DATA): Register it.

Signed-off-by: Zheng Junjie &lt;zhengjunjie@iscas.ac.cn&gt;
Change-Id: I328ca0c01787defcc9d18f4ccd7762c86412cca7
Signed-off-by: Zheng Junjie &lt;zhengjunjie@iscas.ac.cn&gt;
</span></span></td><td>Daniel Ziltener</td></tr>
<tr><td><span title='2024-01-25 23:48:49 +0800'>2024-01-25</span></td><td><a href='/guix/commit/gnu/packages/debug.scm?id=06221e910a5718c7d4ad2dcc7ffad2bc8e92fdc5'>gnu: Add aflplusplus.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/debug.scm (aflplusplus): New variable.

Change-Id: Ibda36187e839d5f533d461444db25a7ba5567f0f
Modified-by: Hilton Chain &lt;hako@ultrarare.space&gt;
Signed-off-by: Hilton Chain &lt;hako@ultrarare.space&gt;
</span></span></td><td>Denis 'GNUtoo' Carikli</td></tr>
<tr><td><span title='2023-12-23 11:17:49 +0100'>2023-12-23</span></td><td><a href='/guix/commit/gnu/packages/debug.scm?id=3320c9704353cea29ae34662f3975bf6b58c87f9'>gnu: rr: Update to 5.7.0.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/debug.scm (rr): Update to 5.7.0.

Change-Id: I5b70f5d266876077b533182ccdcd2160fec6fcc4
Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Greg Hogan</td></tr>
<tr><td><span title='2023-09-15 10:00:10 +0100'>2023-09-15</span></td><td><a href='/guix/commit/gnu/packages/debug.scm?id=a0510561935e3327099df558e9dd9bdffe850441'>gnu: delve: Update to 1.21.0.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/debug.scm (delve): Update to 1.21.0.
[propagated-inputs]: Remove go.

Signed-off-by: Christopher Baines &lt;mail@cbaines.net&gt;
</span></span></td><td>Andrew Jose</td></tr>