[Buildroot] [PATCH] fdk-aac: fix build with GCC 6

[Buildroot] [PATCH] fdk-aac: fix build with GCC 6

[Jörg Krause]

GCC 6 defaults to -std=gnu++14 instead of -std=gnu++98. The C++11 standard does
not allow "narrowing conversions" which is why building fdk-aac with GCC 6
fails:

libAACenc/src/aacEnc_rom.cpp:661:1: error: narrowing conversion of '2180108801u' from 'unsigned int' to 'FIXP_DBL {aka long int}' inside { } [-Wnarrowing]

Use '-std=gnu++98' as suggested by "Porting to GCC 6" [1].

[1] https://gcc.gnu.org/gcc-6/porting_to.html

Signed-off-by: J?rg Krause <joerg.krause@embedded.rocks>
---
 package/fdk-aac/fdk-aac.mk | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/package/fdk-aac/fdk-aac.mk b/package/fdk-aac/fdk-aac.mk
index a872c54..45a3cf5 100644
--- a/package/fdk-aac/fdk-aac.mk
+++ b/package/fdk-aac/fdk-aac.mk
@@ -11,4 +11,7 @@ FDK_AAC_LICENSE_FILES = NOTICE
 
 FDK_AAC_INSTALL_STAGING = YES
 
+# Not compatible with GCC 6 which defaults to GNU++14
+FDK_AAC_CONF_ENV += CXXFLAGS="$(TARGET_CXXFLAGS) -std=gnu++98"
+
 $(eval $(autotools-package))
-- 
2.8.2

[Buildroot] [PATCH] fdk-aac: fix build with GCC 6

[Thomas Petazzoni]

Hello,

On Sun,  1 May 2016 11:18:08 +0200, J?rg Krause wrote:
> GCC 6 defaults to -std=gnu++14 instead of -std=gnu++98. The C++11 standard does
> not allow "narrowing conversions" which is why building fdk-aac with GCC 6
> fails:
> 
> libAACenc/src/aacEnc_rom.cpp:661:1: error: narrowing conversion of '2180108801u' from 'unsigned int' to 'FIXP_DBL {aka long int}' inside { } [-Wnarrowing]
> 
> Use '-std=gnu++98' as suggested by "Porting to GCC 6" [1].
> 
> [1] https://gcc.gnu.org/gcc-6/porting_to.html
> 
> Signed-off-by: J?rg Krause <joerg.krause@embedded.rocks>
> ---
>  package/fdk-aac/fdk-aac.mk | 3 +++
>  1 file changed, 3 insertions(+)

Applied to master, but please report the bug upstream so that they fix
in their source code or build system. Thanks!

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com