pkg/46177: libgcrypt doesn't build using clang

[jonathan+pkgsrc%pinacea.com@localhost]

>Number:         46177
>Category:       pkg
>Synopsis:       libgcrypt doesn't build using clang
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Mar 11 20:10:01 +0000 2012
>Originator:     jonathan buschmann
>Release:        
>Organization:
>Environment:
Darwin host 11.3.0 Darwin Kernel Version 11.3.0: Thu Jan 12 18:48:32 PST 2012; 
root:xnu-1699.24.23~1/RELEASE_I386 i386
>Description:
/bin/sh ../libtool --tag=CC    --mode=compile gcc -DHAVE_CONFIG_H -I. -I..   
-I../src -I../src -I/Users/jonthn/wine32/include -I/usr/include 
-I/Users/jonthn/wine32/include -pipe -O2 -I/Users/jonthn/wine32/include 
-I/usr/include -Wall -MT mpih-div.lo -MD -MP -MF .deps/mpih-div.Tpo -c -o 
mpih-div.lo mpih-div.c
libtool: compile:  gcc -DHAVE_CONFIG_H -I. -I.. -I../src 
-I/Users/jonthn/code/pkgsrc/security/libgcrypt/work/.buildlink/include -pipe 
-O2 -Wall -MT mpih-div.lo -MD -MP -MF .deps/mpih-div.Tpo -c mpih-div.c  
-fno-common -DPIC -o .libs/mpih-div.o
mpih-div.c:84:14: error: invalid use of a cast in a inline asm context 
requiring an l-value: remove the cast or build with -fheinous-gnu-extensions
                udiv_qrnnd(divisor_limb_inverted, dummy,
                ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>How-To-Repeat:
Try to install libgcrypt when using clang as the C compiler.
>Fix:
Add this flag to the Makefile

.if !empty(PKGSRC_COMPILER:Mclang)
CFLAGS+=                -fheinous-gnu-extensions
.endif