[PATCH] build system: choose gnu99 as a C standard

[David Bremner]

Apparently pre 5.1 gcc defaulted to gnu89, but we decided it was ok to
use some c99 features.

'-std=c99' by itself is not enough for notmuch to compile.

'-std=gnu99' seems to work with clang and gcc, so I'm not convinced
configuration support is needed.
---

Our use of c99 loop variable declarations breaks the build on travis,
because old gcc defaults to c89+extensions

 Makefile.local | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Makefile.local b/Makefile.local
index 5587cd2..d1b0585 100644
--- a/Makefile.local
+++ b/Makefile.local
@@ -44,7 +44,8 @@ GPG_FILE=$(SHA1_FILE).asc
 PV_FILE=bindings/python/notmuch/version.py
 
 # Smash together user's values with our extra values
-FINAL_CFLAGS = -DNOTMUCH_VERSION=$(VERSION) $(CPPFLAGS) $(CFLAGS) $(WARN_CFLAGS) $(extra_cflags) $(CONFIGURE_CFLAGS)
+STD_CFLAGS := -std=gnu99
+FINAL_CFLAGS = -DNOTMUCH_VERSION=$(VERSION) $(CPPFLAGS) $(STD_CFLAGS) $(CFLAGS) $(WARN_CFLAGS) $(extra_cflags) $(CONFIGURE_CFLAGS)
 FINAL_CXXFLAGS = $(CPPFLAGS) $(CXXFLAGS) $(WARN_CXXFLAGS) $(extra_cflags) $(extra_cxxflags) $(CONFIGURE_CXXFLAGS)
 FINAL_NOTMUCH_LDFLAGS = $(LDFLAGS) -Lutil -lutil -Llib -lnotmuch
 ifeq ($(LIBDIR_IN_LDCONFIG),0)
-- 
2.9.3