Perl interface: add build-time configuration to allow building with -fPIC

On x86-64 it seems that Git.xs does not link without compiling
the main git objects with -fPIC.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/Makefile b/Makefile
index dda9b9d..aa0618e 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1,11 +1,6 @@
 # The default target of this Makefile is...
 all:
 
-# Define MOZILLA_SHA1 environment variable when running make to make use of
-# a bundled SHA1 routine coming from Mozilla. It is GPL'd and should be fast
-# on non-x86 architectures (e.g. PowerPC), while the OpenSSL version (default
-# choice) has very fast version optimized for i586.
-#
 # Define NO_OPENSSL environment variable if you do not have OpenSSL.
 # This also implies MOZILLA_SHA1.
 #
@@ -39,6 +34,14 @@ all:
 # Define ARM_SHA1 environment variable when running make to make use of
 # a bundled SHA1 routine optimized for ARM.
 #
+# Define MOZILLA_SHA1 environment variable when running make to make use of
+# a bundled SHA1 routine coming from Mozilla. It is GPL'd and should be fast
+# on non-x86 architectures (e.g. PowerPC), while the OpenSSL version (default
+# choice) has very fast version optimized for i586.
+#
+# Define USE_PIC if you need the main git objects to be built with -fPIC
+# in order to build and link perl/Git.so.  x86-64 seems to need this.
+#
 # Define NEEDS_SSL_WITH_CRYPTO if you need -lcrypto with -lssl (Darwin).
 #
 # Define NEEDS_LIBICONV if linking with libc is not enough (Darwin).
@@ -65,13 +68,13 @@ all:
 # Define COLLISION_CHECK below if you believe that SHA1's
 # 1461501637330902918203684832716283019655932542976 hashes do not give you
 # sufficient guarantee that no collisions between objects will ever happen.
-
+#
 # Define USE_NSEC below if you want git to care about sub-second file mtimes
 # and ctimes. Note that you need recent glibc (at least 2.2.4) for this, and
 # it will BREAK YOUR LOCAL DIFFS! show-diff and anything using it will likely
 # randomly break unless your underlying filesystem supports those sub-second
 # times (my ext3 doesn't).
-
+#
 # Define USE_STDEV below if you want git to care about the underlying device
 # change being considered an inode change from the update-cache perspective.
 
@@ -464,6 +467,9 @@ else
 endif
 endif
 endif
+ifdef USE_PIC
+       ALL_CFLAGS += -fPIC
+endif
 ifdef NO_ACCURATE_DIFF
        ALL_CFLAGS += -DNO_ACCURATE_DIFF
 endif