[PATCH/RFC 2/3] compat/regex: hacks to get the gawk regex engine to compile within git

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

The gawk regex engine didn't include stdio.h, and only include
stddef.h if HAVE_STDDEF_H is set.

Adding -DHAVE_STDDEF_H caused some internal errors in by /usr/include
headers, so change the regex.h code to include it unconditionally.

We also need to define -DGAWK so that e.g. "bool", "MAX" and other
similar things used inside gawk get defined.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 Makefile             |    4 ++++
 compat/regex/regex.h |    7 +++++--
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index b4745a5..6704780 100644
--- a/Makefile
+++ b/Makefile
@@ -1443,6 +1443,10 @@ ifdef UNRELIABLE_FSTAT
 	BASIC_CFLAGS += -DUNRELIABLE_FSTAT
 endif
 ifdef NO_REGEX
+	# TODO: How do I compile just regex.o with this flag, not the
+	# whole of Git?
+	BASIC_CFLAGS += -DGAWK
+
 	COMPAT_CFLAGS += -Icompat/regex
 	COMPAT_OBJS += compat/regex/regex.o
 endif
diff --git a/compat/regex/regex.h b/compat/regex/regex.h
index de93327..508bc80 100644
--- a/compat/regex/regex.h
+++ b/compat/regex/regex.h
@@ -22,9 +22,12 @@
 #ifndef _REGEX_H
 #define _REGEX_H 1
 
-#ifdef HAVE_STDDEF_H
+#include <stdio.h>
+/*
+  Git: Was in `#ifdef HAVE_STDDEF_H` in gawk, adding -DHAVE_STDDEF_H makes a
+  *lot* of other things break
+*/
 #include <stddef.h>
-#endif
 
 #ifdef HAVE_SYS_TYPES_H
 #include <sys/types.h>
-- 
1.7.2.1.389.gc3d0b