buildroot/package/multimedia/alsa-utils/alsa-utils-exp10-workaround.patch

From da14c5ab2a6e030c5c56c979b8eb3ca071890876 Mon Sep 17 00:00:00 2001
From: Peter Korsgaard <jacmet@sunsite.dk>
Date: Mon, 14 Mar 2011 09:19:18 +0100
Subject: [PATCH] alsamixer: fix build on uClibc

exp10 is a glibc extension, which isn't supported on uClibc. Luckily,
exp10() is trivial to compute based on exp(), so add a wrapper for
the uClibc case.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
---
 alsamixer/volume_mapping.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/alsamixer/volume_mapping.c b/alsamixer/volume_mapping.c
index 9cacad8..1c0d7c4 100644
--- a/alsamixer/volume_mapping.c
+++ b/alsamixer/volume_mapping.c
@@ -37,6 +37,11 @@
 #include <stdbool.h>
 #include "volume_mapping.h"
 
+#ifdef __UCLIBC__
+/* 10^x = 10^(log e^x) = (e^x)^log10 = e^(x * log 10) */
+#define exp10(x) (exp((x) * log(10)))
+#endif /* __UCLIBC__ */
+
 #define MAX_LINEAR_DB_SCALE	24
 
 static inline bool use_linear_dB_scale(long dBmin, long dBmax)
-- 
1.7.2.3