diff --git a/.clang-format b/.clang-format
index 04c1f8b3a2..02ab139b96 100644
--- a/.clang-format
+++ b/.clang-format
@@ -79,3 +79,4 @@ Standard: Cpp11
 ContinuationIndentWidth: 8
 RemoveParentheses: ReturnStatement
 RemoveSemicolon: true
+SpaceBeforeParens: ControlStatementsExceptControlMacros
diff --git a/.clang-format.headers b/.clang-format.headers
index ff9370413e..607196547a 100644
--- a/.clang-format.headers
+++ b/.clang-format.headers
@@ -67,3 +67,4 @@ Standard: Cpp11
 ContinuationIndentWidth: 8
 RemoveParentheses: ReturnStatement
 RemoveSemicolon: true
+SpaceBeforeParens: ControlStatementsExceptControlMacros
diff --git a/lib/isc/os.c b/lib/isc/os.c
index 9465234f96..aa48c31791 100644
--- a/lib/isc/os.c
+++ b/lib/isc/os.c
@@ -87,8 +87,9 @@ sched_affinity_ncpus(void) {
 		int i, n = 0;
 
 		for (i = 0; i < CPU_SETSIZE; ++i) {
-			if (CPU_ISSET(i, &cpus))
+			if (CPU_ISSET(i, &cpus)) {
 				++n;
+			}
 		}
 		return n;
 #endif
@@ -115,8 +116,9 @@ cpuset_affinity_ncpus(void) {
 	if (result != -1) {
 		int i, n = 0;
 		for (i = 0; i < CPU_SETSIZE; ++i) {
-			if (CPU_ISSET(i, &cpus))
+			if (CPU_ISSET(i, &cpus)) {
 				++n;
+			}
 		}
 		return n;
 	}
diff --git a/lib/isc/picohttpparser.c b/lib/isc/picohttpparser.c
index 0545624e54..933137714b 100644
--- a/lib/isc/picohttpparser.c
+++ b/lib/isc/picohttpparser.c
@@ -612,8 +612,9 @@ phr_decode_chunked(struct phr_chunked_decoder *decoder, char *buf,
 		case CHUNKED_IN_CHUNK_SIZE:
 			for (;; ++src) {
 				int v;
-				if (src == bufsz)
+				if (src == bufsz) {
 					goto Exit;
+				}
 				if ((v = decode_hex(buf[src])) == -1) {
 					if (decoder->_hex_count == 0) {
 						ret = -1;
@@ -650,10 +651,12 @@ phr_decode_chunked(struct phr_chunked_decoder *decoder, char *buf,
 			/* RFC 7230 A.2 "Line folding in chunk extensions is
 			 * disallowed" */
 			for (;; ++src) {
-				if (src == bufsz)
+				if (src == bufsz) {
 					goto Exit;
-				if (buf[src] == '\012')
+				}
+				if (buf[src] == '\012') {
 					break;
+				}
 			}
 			++src;
 			if (decoder->bytes_left_in_chunk == 0) {
@@ -670,16 +673,18 @@ phr_decode_chunked(struct phr_chunked_decoder *decoder, char *buf,
 		case CHUNKED_IN_CHUNK_DATA: {
 			size_t avail = bufsz - src;
 			if (avail < decoder->bytes_left_in_chunk) {
-				if (dst != src)
+				if (dst != src) {
 					memmove(buf + dst, buf + src, avail);
+				}
 				src += avail;
 				dst += avail;
 				decoder->bytes_left_in_chunk -= avail;
 				goto Exit;
 			}
-			if (dst != src)
+			if (dst != src) {
 				memmove(buf + dst, buf + src,
 					decoder->bytes_left_in_chunk);
+			}
 			src += decoder->bytes_left_in_chunk;
 			dst += decoder->bytes_left_in_chunk;
 			decoder->bytes_left_in_chunk = 0;
@@ -688,10 +693,12 @@ phr_decode_chunked(struct phr_chunked_decoder *decoder, char *buf,
 		/* fallthru */
 		case CHUNKED_IN_CHUNK_CRLF:
 			for (;; ++src) {
-				if (src == bufsz)
+				if (src == bufsz) {
 					goto Exit;
-				if (buf[src] != '\015')
+				}
+				if (buf[src] != '\015') {
 					break;
+				}
 			}
 			if (buf[src] != '\012') {
 				ret = -1;
@@ -702,21 +709,26 @@ phr_decode_chunked(struct phr_chunked_decoder *decoder, char *buf,
 			break;
 		case CHUNKED_IN_TRAILERS_LINE_HEAD:
 			for (;; ++src) {
-				if (src == bufsz)
+				if (src == bufsz) {
 					goto Exit;
-				if (buf[src] != '\015')
+				}
+				if (buf[src] != '\015') {
 					break;
+				}
 			}
-			if (buf[src++] == '\012')
+			if (buf[src++] == '\012') {
 				goto Complete;
+			}
 			decoder->_state = CHUNKED_IN_TRAILERS_LINE_MIDDLE;
 		/* fallthru */
 		case CHUNKED_IN_TRAILERS_LINE_MIDDLE:
 			for (;; ++src) {
-				if (src == bufsz)
+				if (src == bufsz) {
 					goto Exit;
-				if (buf[src] == '\012')
+				}
+				if (buf[src] == '\012') {
 					break;
+				}
 			}
 			++src;
 			decoder->_state = CHUNKED_IN_TRAILERS_LINE_HEAD;
@@ -729,8 +741,9 @@ phr_decode_chunked(struct phr_chunked_decoder *decoder, char *buf,
 Complete:
 	ret = bufsz - src;
 Exit:
-	if (dst != src)
+	if (dst != src) {
 		memmove(buf + dst, buf + src, bufsz - src);
+	}
 	*_bufsz = dst;
 	/* if incomplete but the overhead of the chunked encoding is >=100KB and
 	 * >80%, signal an error */
diff --git a/lib/isc/string.c b/lib/isc/string.c
index c71a9e661e..a9876a67a0 100644
--- a/lib/isc/string.c
+++ b/lib/isc/string.c
@@ -125,11 +125,13 @@ strnstr(const char *s, const char *find, size_t slen) {
 		len = strlen(find);
 		do {
 			do {
-				if (slen-- < 1 || (sc = *s++) == '\0')
+				if (slen-- < 1 || (sc = *s++) == '\0') {
 					return NULL;
+				}
 			} while (sc != c);
-			if (len > slen)
+			if (len > slen) {
 				return NULL;
+			}
 		} while (strncmp(s, find, len) != 0);
 		s--;
 	}