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-rw-r--r--target/linux/generic/pending-3.18/270-uapi-libc-compat-add-fallback-for-unsupported-libcs.patch102
1 files changed, 102 insertions, 0 deletions
diff --git a/target/linux/generic/pending-3.18/270-uapi-libc-compat-add-fallback-for-unsupported-libcs.patch b/target/linux/generic/pending-3.18/270-uapi-libc-compat-add-fallback-for-unsupported-libcs.patch
new file mode 100644
index 0000000..6789599
--- /dev/null
+++ b/target/linux/generic/pending-3.18/270-uapi-libc-compat-add-fallback-for-unsupported-libcs.patch
@@ -0,0 +1,102 @@
+From c6bdd0d302119819de72439972d0462c26ef9eda Mon Sep 17 00:00:00 2001
+From: Felix Janda <felix.janda@posteo.de>
+Date: Sun, 12 Nov 2017 13:30:17 -0500
+Subject: uapi libc compat: add fallback for unsupported libcs
+
+libc-compat.h aims to prevent symbol collisions between uapi and libc
+headers for each supported libc. This requires continuous coordination
+between them.
+
+The goal of this commit is to improve the situation for libcs (such as
+musl) which are not yet supported and/or do not wish to be explicitly
+supported, while not affecting supported libcs. More precisely, with
+this commit, unsupported libcs can request the suppression of any
+specific uapi definition by defining the correspondings _UAPI_DEF_*
+macro as 0. This can fix symbol collisions for them, as long as the
+libc headers are included before the uapi headers. Inclusion in the
+other order is outside the scope of this commit.
+
+All infrastructure in order to enable this fallback for unsupported
+libcs is already in place, except that libc-compat.h unconditionally
+defines all _UAPI_DEF_* macros to 1 for all unsupported libcs so that
+any previous definitions are ignored. In order to fix this, this commit
+merely makes these definitions conditional.
+
+This commit together with the musl libc commit
+
+http://git.musl-libc.org/cgit/musl/commit/?id=04983f2272382af92eb8f8838964ff944fbb8258
+
+fixes for example the following compiler errors when <linux/in6.h> is
+included after musl's <netinet/in.h>:
+
+./linux/in6.h:32:8: error: redefinition of 'struct in6_addr'
+./linux/in6.h:49:8: error: redefinition of 'struct sockaddr_in6'
+./linux/in6.h:59:8: error: redefinition of 'struct ipv6_mreq'
+
+The comments referencing glibc are still correct, but this file is not
+only used for glibc any more.
+
+Signed-off-by: Felix Janda <felix.janda@posteo.de>
+Reviewed-by: Hauke Mehrtens <hauke@hauke-m.de>
+---
+ include/uapi/linux/libc-compat.h | 55 +++++++++++++++++++++++++++++++++++++++-
+ 1 file changed, 54 insertions(+), 1 deletion(-)
+
+--- a/include/uapi/linux/libc-compat.h
++++ b/include/uapi/linux/libc-compat.h
+@@ -110,27 +110,54 @@
+
+ /* If we did not see any headers from any supported C libraries,
+ * or we are being included in the kernel, then define everything
+- * that we need. */
++ * that we need. Check for previous __UAPI_* definitions to give
++ * unsupported C libraries a way to opt out of any kernel definition. */
+ #else /* !defined(__GLIBC__) */
+
+ /* Definitions for in.h */
++#ifndef __UAPI_DEF_IN_ADDR
+ #define __UAPI_DEF_IN_ADDR 1
++#endif
++#ifndef __UAPI_DEF_IN_IPPROTO
+ #define __UAPI_DEF_IN_IPPROTO 1
++#endif
++#ifndef __UAPI_DEF_IN_PKTINFO
+ #define __UAPI_DEF_IN_PKTINFO 1
++#endif
++#ifndef __UAPI_DEF_IP_MREQ
+ #define __UAPI_DEF_IP_MREQ 1
++#endif
++#ifndef __UAPI_DEF_SOCKADDR_IN
+ #define __UAPI_DEF_SOCKADDR_IN 1
++#endif
++#ifndef __UAPI_DEF_IN_CLASS
+ #define __UAPI_DEF_IN_CLASS 1
++#endif
+
+ /* Definitions for in6.h */
++#ifndef __UAPI_DEF_IN6_ADDR
+ #define __UAPI_DEF_IN6_ADDR 1
++#endif
++#ifndef __UAPI_DEF_IN6_ADDR_ALT
+ #define __UAPI_DEF_IN6_ADDR_ALT 1
++#endif
++#ifndef __UAPI_DEF_SOCKADDR_IN6
+ #define __UAPI_DEF_SOCKADDR_IN6 1
++#endif
++#ifndef __UAPI_DEF_IPV6_MREQ
+ #define __UAPI_DEF_IPV6_MREQ 1
++#endif
++#ifndef __UAPI_DEF_IPPROTO_V6
+ #define __UAPI_DEF_IPPROTO_V6 1
++#endif
++#ifndef __UAPI_DEF_IPV6_OPTIONS
+ #define __UAPI_DEF_IPV6_OPTIONS 1
++#endif
+
+ /* Definitions for xattr.h */
++#ifndef __UAPI_DEF_XATTR
+ #define __UAPI_DEF_XATTR 1
++#endif
+
+ #endif /* __GLIBC__ */
+