[PATCH 1/2] Makefile: refactor regex compat support

[Jeff King <peff@peff.net>]

There was no tweakable knob to use the regex compat code; it
was embedded in the mingw build. Since other platforms may
want to use it, let's factor it out in the usual way for
build configuration knobs.

Signed-off-by: Jeff King <peff@peff.net>
---
This should behave the same as before on all platforms. The only one I
might have screwed up by doing it wrong is mingw, but I have no machine
to test on. Johannes, can you confirm that it is right?

 Makefile |   11 +++++++++--
 1 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 04bf8b1..a1e4e45 100644
--- a/Makefile
+++ b/Makefile
@@ -182,6 +182,8 @@ all::
 #
 # Define NO_CROSS_DIRECTORY_HARDLINKS if you plan to distribute the installed
 # programs as a tar, where bin/ and libexec/ might be on different file systems.
+#
+# Define NO_REGEX if you have no or inferior regex support in your C library.
 
 GIT-VERSION-FILE: .FORCE-GIT-VERSION-FILE
 	@$(SHELL_PATH) ./GIT-VERSION-GEN
@@ -863,10 +865,11 @@ ifneq (,$(findstring MINGW,$(uname_S)))
 	USE_WIN32_MMAP = YesPlease
 	UNRELIABLE_FSTAT = UnfortunatelyYes
 	OBJECT_CREATION_USES_RENAMES = UnfortunatelyNeedsTo
-	COMPAT_CFLAGS += -D__USE_MINGW_ACCESS -DNOGDI -Icompat -Icompat/regex -Icompat/fnmatch
+	NO_REGEX = YesPlease
+	COMPAT_CFLAGS += -D__USE_MINGW_ACCESS -DNOGDI -Icompat -Icompat/fnmatch
 	COMPAT_CFLAGS += -DSNPRINTF_SIZE_CORR=1
 	COMPAT_CFLAGS += -DSTRIP_EXTENSION=\".exe\"
-	COMPAT_OBJS += compat/mingw.o compat/fnmatch/fnmatch.o compat/regex/regex.o compat/winansi.o
+	COMPAT_OBJS += compat/mingw.o compat/fnmatch/fnmatch.o compat/winansi.o
 	EXTLIBS += -lws2_32
 	X = .exe
 endif
@@ -1157,6 +1160,10 @@ endif
 ifdef UNRELIABLE_FSTAT
 	BASIC_CFLAGS += -DUNRELIABLE_FSTAT
 endif
+ifdef NO_REGEX
+	COMPAT_CFLAGS += -Icompat/regex
+	COMPAT_OBJS += compat/regex/regex.o
+endif
 
 ifeq ($(TCLTK_PATH),)
 NO_TCLTK=NoThanks
-- 
1.6.3.2.225.gb8364.dirty