diff --git a/makeflags b/makeflags
index bae1765..d1f6dcf 100644
--- a/makeflags
+++ b/makeflags
@@ -1,4 +1,4 @@
-CCFLAGS  = -Wall -Wextra -Werror -O3 -march=native -I../include -ggdb -fpic
+CCFLAGS  = -Wall -Wextra -Werror -O3 -march=native -I../include -ggdb -fpic -D_FILE_OFFSET_BITS=64
 # CCFLAGS  = -Wall -Wextra -Werror -O0 -I../include -ggdb -fpic
 CFLAGS   = $(CCFLAGS) -std=c99
 CXXFLAGS = $(CCFLAGS) -std=c++11 -Wold-style-cast
diff --git a/test/limits.cc b/test/limits.cc
index b9f3efc..b906f4f 100644
--- a/test/limits.cc
+++ b/test/limits.cc
@@ -126,13 +126,7 @@ test_cast_0x80000000_to_things()
 {
 	auto sv = 0x80000000LL;
 	auto uv = 0x80000000ULL;
-	if (sizeof(off_t) == 4) {
-		SHOULD_FAIL(ranged_cast<off_t>(sv));
-	} else if (sizeof(off_t) == 8) {
-		SHOULD_PASS(ranged_cast<off_t>(sv), sv);
-	} else {
-		assert(!"unhandled case, please add code for off_t here");
-	}
+	SHOULD_PASS(ranged_cast<off_t>(sv), sv);
 	SHOULD_PASS(ranged_cast<uint64_t>(uv), uv);
 	SHOULD_PASS(ranged_cast<uint32_t>(uv), uv);
 	SHOULD_FAIL(ranged_cast<uint16_t>(uv));
@@ -171,13 +165,7 @@ test_cast_0xffffffff_to_things()
 {
 	auto sv = 0xffffffffLL;
 	auto uv = 0xffffffffULL;
-	if (sizeof(off_t) == 4) {
-		SHOULD_FAIL(ranged_cast<off_t>(sv));
-	} else if (sizeof(off_t) == 8) {
-		SHOULD_PASS(ranged_cast<off_t>(sv), sv);
-	} else {
-		assert(!"unhandled case, please add code for off_t here");
-	}
+	SHOULD_PASS(ranged_cast<off_t>(sv), sv);
 	SHOULD_PASS(ranged_cast<uint64_t>(uv), uv);
 	SHOULD_PASS(ranged_cast<uint32_t>(uv), uv);
 	SHOULD_FAIL(ranged_cast<uint16_t>(uv));
@@ -216,13 +204,7 @@ test_cast_0xfffffffff_to_things()
 {
 	auto sv = 0xfffffffffLL;
 	auto uv = 0xfffffffffULL;
-	if (sizeof(off_t) == 4) {
-		SHOULD_FAIL(ranged_cast<off_t>(sv));
-	} else if (sizeof(off_t) == 8) {
-		SHOULD_PASS(ranged_cast<off_t>(sv), sv);
-	} else {
-		assert(!"unhandled case, please add code for off_t here");
-	}
+	SHOULD_PASS(ranged_cast<off_t>(sv), sv);
 	SHOULD_PASS(ranged_cast<uint64_t>(uv), uv);
 	SHOULD_FAIL(ranged_cast<uint32_t>(uv));
 	SHOULD_FAIL(ranged_cast<uint16_t>(uv));