diff --git a/mk/precompiled-headers.mk b/mk/precompiled-headers.mk
index 1c0452dc2..500c99e4a 100644
--- a/mk/precompiled-headers.mk
+++ b/mk/precompiled-headers.mk
@@ -21,13 +21,13 @@ clean-files += $(GCH) $(PCH)
 
 ifeq ($(PRECOMPILE_HEADERS), 1)
 
-  ifeq ($(CXX), g++)
+  ifeq ($(findstring g++,$(CXX)), g++)
 
     GLOBAL_CXXFLAGS_PCH += -include $(buildprefix)precompiled-headers.h -Winvalid-pch
 
     GLOBAL_ORDER_AFTER += $(GCH)
 
-  else ifeq ($(CXX), clang++)
+  else ifeq ($(findstring clang++,$(CXX)), clang++)
 
     GLOBAL_CXXFLAGS_PCH += -include-pch $(PCH) -Winvalid-pch
 
diff --git a/src/libstore/derivations.cc b/src/libstore/derivations.cc
index 157fc1db1..c88bb3c6d 100644
--- a/src/libstore/derivations.cc
+++ b/src/libstore/derivations.cc
@@ -24,6 +24,7 @@ std::optional<StorePath> DerivationOutput::pathOpt(const Store & store, std::str
     }, output);
 }
 
+
 bool derivationIsCA(DerivationType dt) {
     switch (dt) {
     case DerivationType::Regular: return false;
diff --git a/src/libutil/util.cc b/src/libutil/util.cc
index 93798a765..a0a8ff4d3 100644
--- a/src/libutil/util.cc
+++ b/src/libutil/util.cc
@@ -1581,7 +1581,7 @@ AutoCloseFD createUnixDomainSocket(const Path & path, mode_t mode)
 
     struct sockaddr_un addr;
     addr.sun_family = AF_UNIX;
-    if (path.size() >= sizeof(addr.sun_path))
+    if (path.size() + 1 >= sizeof(addr.sun_path))
         throw Error("socket path '%1%' is too long", path);
     strcpy(addr.sun_path, path.c_str());