diff --git a/dev-db/postgresql/postgresql-11.19.ebuild b/dev-db/postgresql/postgresql-11.19.ebuild
index ce6c8b0a188b1..90e09a3b7bb5e 100644
--- a/dev-db/postgresql/postgresql-11.19.ebuild
+++ b/dev-db/postgresql/postgresql-11.19.ebuild
@@ -4,7 +4,7 @@
 EAPI=8
 
 PYTHON_COMPAT=( python3_{9,10,11} )
-LLVM_MAX_SLOT=16
+LLVM_MAX_SLOT=15
 
 inherit flag-o-matic linux-info llvm pam python-single-r1 systemd tmpfiles
 
@@ -37,8 +37,8 @@ icu? ( dev-libs/icu:= )
 kerberos? ( virtual/krb5 )
 ldap? ( net-nds/openldap:= )
 llvm? (
-	<sys-devel/llvm-17:=
-	<sys-devel/clang-17:=
+	<sys-devel/llvm-16:=
+	<sys-devel/clang-16:=
 )
 pam? ( sys-libs/pam )
 perl? ( >=dev-lang/perl-5.8:= )
diff --git a/dev-db/postgresql/postgresql-11.20.ebuild b/dev-db/postgresql/postgresql-11.20.ebuild
index ce6c8b0a188b1..90e09a3b7bb5e 100644
--- a/dev-db/postgresql/postgresql-11.20.ebuild
+++ b/dev-db/postgresql/postgresql-11.20.ebuild
@@ -4,7 +4,7 @@
 EAPI=8
 
 PYTHON_COMPAT=( python3_{9,10,11} )
-LLVM_MAX_SLOT=16
+LLVM_MAX_SLOT=15
 
 inherit flag-o-matic linux-info llvm pam python-single-r1 systemd tmpfiles
 
@@ -37,8 +37,8 @@ icu? ( dev-libs/icu:= )
 kerberos? ( virtual/krb5 )
 ldap? ( net-nds/openldap:= )
 llvm? (
-	<sys-devel/llvm-17:=
-	<sys-devel/clang-17:=
+	<sys-devel/llvm-16:=
+	<sys-devel/clang-16:=
 )
 pam? ( sys-libs/pam )
 perl? ( >=dev-lang/perl-5.8:= )
diff --git a/dev-db/postgresql/postgresql-12.14.ebuild b/dev-db/postgresql/postgresql-12.14.ebuild
index 8946d4c8a1f88..54fa5c1efd529 100644
--- a/dev-db/postgresql/postgresql-12.14.ebuild
+++ b/dev-db/postgresql/postgresql-12.14.ebuild
@@ -4,7 +4,7 @@
 EAPI=8
 
 PYTHON_COMPAT=( python3_{9,10,11} )
-LLVM_MAX_SLOT=16
+LLVM_MAX_SLOT=15
 
 inherit flag-o-matic linux-info llvm pam python-single-r1 systemd tmpfiles
 
@@ -37,8 +37,8 @@ icu? ( dev-libs/icu:= )
 kerberos? ( virtual/krb5 )
 ldap? ( net-nds/openldap:= )
 llvm? (
-	<sys-devel/llvm-17:=
-	<sys-devel/clang-17:=
+	<sys-devel/llvm-16:=
+	<sys-devel/clang-16:=
 )
 pam? ( sys-libs/pam )
 perl? ( >=dev-lang/perl-5.8:= )
diff --git a/dev-db/postgresql/postgresql-12.15.ebuild b/dev-db/postgresql/postgresql-12.15.ebuild
index 8946d4c8a1f88..54fa5c1efd529 100644
--- a/dev-db/postgresql/postgresql-12.15.ebuild
+++ b/dev-db/postgresql/postgresql-12.15.ebuild
@@ -4,7 +4,7 @@
 EAPI=8
 
 PYTHON_COMPAT=( python3_{9,10,11} )
-LLVM_MAX_SLOT=16
+LLVM_MAX_SLOT=15
 
 inherit flag-o-matic linux-info llvm pam python-single-r1 systemd tmpfiles
 
@@ -37,8 +37,8 @@ icu? ( dev-libs/icu:= )
 kerberos? ( virtual/krb5 )
 ldap? ( net-nds/openldap:= )
 llvm? (
-	<sys-devel/llvm-17:=
-	<sys-devel/clang-17:=
+	<sys-devel/llvm-16:=
+	<sys-devel/clang-16:=
 )
 pam? ( sys-libs/pam )
 perl? ( >=dev-lang/perl-5.8:= )
diff --git a/dev-db/postgresql/postgresql-13.10.ebuild b/dev-db/postgresql/postgresql-13.10.ebuild
index a613f0d930f4a..9dc8d9d0c8878 100644
--- a/dev-db/postgresql/postgresql-13.10.ebuild
+++ b/dev-db/postgresql/postgresql-13.10.ebuild
@@ -4,7 +4,7 @@
 EAPI=8
 
 PYTHON_COMPAT=( python3_{9,10,11} )
-LLVM_MAX_SLOT=16
+LLVM_MAX_SLOT=15
 
 inherit flag-o-matic linux-info llvm pam python-single-r1 systemd tmpfiles
 
@@ -37,8 +37,8 @@ icu? ( dev-libs/icu:= )
 kerberos? ( virtual/krb5 )
 ldap? ( net-nds/openldap:= )
 llvm? (
-	<sys-devel/llvm-17:=
-	<sys-devel/clang-17:=
+	<sys-devel/llvm-16:=
+	<sys-devel/clang-16:=
 )
 pam? ( sys-libs/pam )
 perl? ( >=dev-lang/perl-5.8:= )
diff --git a/dev-db/postgresql/postgresql-13.11.ebuild b/dev-db/postgresql/postgresql-13.11.ebuild
index a613f0d930f4a..9dc8d9d0c8878 100644
--- a/dev-db/postgresql/postgresql-13.11.ebuild
+++ b/dev-db/postgresql/postgresql-13.11.ebuild
@@ -4,7 +4,7 @@
 EAPI=8
 
 PYTHON_COMPAT=( python3_{9,10,11} )
-LLVM_MAX_SLOT=16
+LLVM_MAX_SLOT=15
 
 inherit flag-o-matic linux-info llvm pam python-single-r1 systemd tmpfiles
 
@@ -37,8 +37,8 @@ icu? ( dev-libs/icu:= )
 kerberos? ( virtual/krb5 )
 ldap? ( net-nds/openldap:= )
 llvm? (
-	<sys-devel/llvm-17:=
-	<sys-devel/clang-17:=
+	<sys-devel/llvm-16:=
+	<sys-devel/clang-16:=
 )
 pam? ( sys-libs/pam )
 perl? ( >=dev-lang/perl-5.8:= )
diff --git a/dev-db/postgresql/postgresql-14.7.ebuild b/dev-db/postgresql/postgresql-14.7.ebuild
index d820d2cf78e21..ab22a5e7b1572 100644
--- a/dev-db/postgresql/postgresql-14.7.ebuild
+++ b/dev-db/postgresql/postgresql-14.7.ebuild
@@ -4,7 +4,7 @@
 EAPI=8
 
 PYTHON_COMPAT=( python3_{9,10,11} )
-LLVM_MAX_SLOT=16
+LLVM_MAX_SLOT=15
 
 inherit flag-o-matic linux-info llvm pam python-single-r1 systemd tmpfiles
 
@@ -37,8 +37,8 @@ icu? ( dev-libs/icu:= )
 kerberos? ( virtual/krb5 )
 ldap? ( net-nds/openldap:= )
 llvm? (
-	 <sys-devel/llvm-17:=
-	 <sys-devel/clang-17:=
+	 <sys-devel/llvm-16:=
+	 <sys-devel/clang-16:=
 )
 lz4? ( app-arch/lz4 )
 pam? ( sys-libs/pam )
diff --git a/dev-db/postgresql/postgresql-14.8.ebuild b/dev-db/postgresql/postgresql-14.8.ebuild
index d820d2cf78e21..ab22a5e7b1572 100644
--- a/dev-db/postgresql/postgresql-14.8.ebuild
+++ b/dev-db/postgresql/postgresql-14.8.ebuild
@@ -4,7 +4,7 @@
 EAPI=8
 
 PYTHON_COMPAT=( python3_{9,10,11} )
-LLVM_MAX_SLOT=16
+LLVM_MAX_SLOT=15
 
 inherit flag-o-matic linux-info llvm pam python-single-r1 systemd tmpfiles
 
@@ -37,8 +37,8 @@ icu? ( dev-libs/icu:= )
 kerberos? ( virtual/krb5 )
 ldap? ( net-nds/openldap:= )
 llvm? (
-	 <sys-devel/llvm-17:=
-	 <sys-devel/clang-17:=
+	 <sys-devel/llvm-16:=
+	 <sys-devel/clang-16:=
 )
 lz4? ( app-arch/lz4 )
 pam? ( sys-libs/pam )
diff --git a/dev-db/postgresql/postgresql-15.2.ebuild b/dev-db/postgresql/postgresql-15.2.ebuild
index 12f67d14eccd7..af00c91f6a606 100644
--- a/dev-db/postgresql/postgresql-15.2.ebuild
+++ b/dev-db/postgresql/postgresql-15.2.ebuild
@@ -4,7 +4,7 @@
 EAPI=8
 
 PYTHON_COMPAT=( python3_{9,10,11} )
-LLVM_MAX_SLOT=16
+LLVM_MAX_SLOT=15
 
 inherit flag-o-matic linux-info llvm pam python-single-r1 systemd tmpfiles
 
@@ -37,8 +37,8 @@ icu? ( dev-libs/icu:= )
 kerberos? ( virtual/krb5 )
 ldap? ( net-nds/openldap:= )
 llvm? (
-	<sys-devel/llvm-17:=
-	<sys-devel/clang-17:=
+	<sys-devel/llvm-16:=
+	<sys-devel/clang-16:=
 )
 lz4? ( app-arch/lz4 )
 pam? ( sys-libs/pam )
diff --git a/dev-db/postgresql/postgresql-15.3.ebuild b/dev-db/postgresql/postgresql-15.3.ebuild
index 12f67d14eccd7..af00c91f6a606 100644
--- a/dev-db/postgresql/postgresql-15.3.ebuild
+++ b/dev-db/postgresql/postgresql-15.3.ebuild
@@ -4,7 +4,7 @@
 EAPI=8
 
 PYTHON_COMPAT=( python3_{9,10,11} )
-LLVM_MAX_SLOT=16
+LLVM_MAX_SLOT=15
 
 inherit flag-o-matic linux-info llvm pam python-single-r1 systemd tmpfiles
 
@@ -37,8 +37,8 @@ icu? ( dev-libs/icu:= )
 kerberos? ( virtual/krb5 )
 ldap? ( net-nds/openldap:= )
 llvm? (
-	<sys-devel/llvm-17:=
-	<sys-devel/clang-17:=
+	<sys-devel/llvm-16:=
+	<sys-devel/clang-16:=
 )
 lz4? ( app-arch/lz4 )
 pam? ( sys-libs/pam )