Can not compile on FreeBSD 13

[juanmitaboada]

After a fresh clone from the repo and trying with gmake, I get the next error:

$ gmake
cc -std=c99 -pedantic -c -O3 -fPIC  -I/usr/local/opt/openssl/include -Wall -W -Wstrict-prototypes -Wwrite-strings -Wno-missing-field-initializers -g -ggdb alloc.c
cc -std=c99 -pedantic -c -O3 -fPIC  -I/usr/local/opt/openssl/include -Wall -W -Wstrict-prototypes -Wwrite-strings -Wno-missing-field-initializers -g -ggdb net.c
cc -std=c99 -pedantic -c -O3 -fPIC  -I/usr/local/opt/openssl/include -Wall -W -Wstrict-prototypes -Wwrite-strings -Wno-missing-field-initializers -g -ggdb hiredis.c
cc -std=c99 -pedantic -c -O3 -fPIC  -I/usr/local/opt/openssl/include -Wall -W -Wstrict-prototypes -Wwrite-strings -Wno-missing-field-initializers -g -ggdb sds.c
cc -std=c99 -pedantic -c -O3 -fPIC  -I/usr/local/opt/openssl/include -Wall -W -Wstrict-prototypes -Wwrite-strings -Wno-missing-field-initializers -g -ggdb async.c
cc -std=c99 -pedantic -c -O3 -fPIC  -I/usr/local/opt/openssl/include -Wall -W -Wstrict-prototypes -Wwrite-strings -Wno-missing-field-initializers -g -ggdb read.c
read.c:312:61: warning: '_Generic' is a C11 extension [-Wc11-extensions]
                if (buf[0] == '\0' || eptr != &buf[len] || !isfinite(d)) {
                                                            ^
/usr/include/math.h:111:21: note: expanded from macro 'isfinite'
#define isfinite(x) __fp_type_select(x, __isfinitef, __isfinite, __isfinitel)
                    ^
/usr/include/math.h:82:39: note: expanded from macro '__fp_type_select'
#define __fp_type_select(x, f, d, ld) _Generic((x),                     \
                                      ^
1 warning generated.
cc -std=c99 -pedantic -c -O3 -fPIC  -I/usr/local/opt/openssl/include -Wall -W -Wstrict-prototypes -Wwrite-strings -Wno-missing-field-initializers -g -ggdb sockcompat.c
cc -shared -Wl,-soname,libhiredis.so.1.0.1-dev -o libhiredis.so alloc.o net.o hiredis.o sds.o async.o read.o sockcompat.o 
ar rcs libhiredis.a alloc.o net.o hiredis.o sds.o async.o read.o sockcompat.o
cc -std=c99 -pedantic -c -O3 -fPIC  -I/usr/local/opt/openssl/include -Wall -W -Wstrict-prototypes -Wwrite-strings -Wno-missing-field-initializers -g -ggdb test.c
test.c:615:15: warning: '_Generic' is a C11 extension [-Wc11-extensions]
              isinf(((redisReply*)reply)->dval) &&
              ^
/usr/include/math.h:112:18: note: expanded from macro 'isinf'
#define isinf(x) __fp_type_select(x, __isinff, __isinf, __isinfl)
                 ^
/usr/include/math.h:82:39: note: expanded from macro '__fp_type_select'
#define __fp_type_select(x, f, d, ld) _Generic((x),                     \
                                      ^
1 warning generated.
cc -o hiredis-test -O3 -fPIC  -I/usr/local/opt/openssl/include -Wall -W -Wstrict-prototypes -Wwrite-strings -Wno-missing-field-initializers -g -ggdb -I. test.o libhiredis.a  
ld: error: undefined symbol: __isfinite
>>> referenced by read.c:312
>>>               read.o:(redisReaderGetReply) in archive libhiredis.a
cc: error: linker command failed with exit code 1 (use -v to see invocation)
gmake: *** [Makefile:211: hiredis-test] Error 1

[michael-grunder]

I only scanned the linked topics, but this appears to be a problem upstream in FreeBSD's math.h header.

TL;DR: We're compiling with -std=c99 but for some reason, the C11 _Generic feature is being invoked. You can attempt to compile without -pedantic although the error we get is slightly different than the others I link below.

See:
igraph/igraph#1748
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=254714

[ac000]

@juanmitaboada The following patch will make it build on FreeBSD (below is tested on 13.0)

diff --git a/Makefile b/Makefile
index f30c2ac..87c79e1 100644
--- a/Makefile
+++ b/Makefile
@@ -92,6 +92,10 @@ else
   SSL_LDFLAGS+=-L$(OPENSSL_PREFIX)/lib -lssl -lcrypto
 endif
 
+ifeq ($(uname_S),FreeBSD)
+  LDFLAGS+=-lm
+endif
+
 ifeq ($(uname_S),SunOS)
   IS_SUN_CC=$(shell sh -c '$(CC) -V 2>&1 |egrep -i -c "sun|studio"')
   ifeq ($(IS_SUN_CC),1)
@@ -231,7 +235,7 @@ check: hiredis-test
        TEST_SSL=$(USE_SSL) ./test.sh
 
 .c.o:
-       $(CC) -std=c99 -pedantic -c $(REAL_CFLAGS) $<
+       $(CC) -std=c99 -c $(REAL_CFLAGS) $<
 
 clean:
        rm -rf $(DYLIBNAME) $(STLIBNAME) $(SSL_DYLIBNAME) $(SSL_STLIBNAME) $(TESTS) $(PKGCONFNAME) examples/hiredis-example* *.o *.gcda *.gcno *.gcov

Or you can leave -pedantic in and compile with GCC I.e gmake CC=gcc

[michael-grunder]

See #1026

@ac000 I tweaked your changes a little bit to keep -pedantic in FreeBSD if the compiler is GCC. Probably not a big deal either way but if possible I'd prefer not to pessimize the build.