But in EPICS 7, registerRecordDeviceDriver.pl complains:
Syntax error in 'breaktable(ZX47-55LN+_142.8MHz) {'

Not very informative, but let's try with quotes. Now the error is:
Illegal breakpoint table name 'ZX47-55LN+_142.8MHz'
       Identifiers are used in C code so must start with a letter, followed
       by letters, digits and/or underscore characters only.

Why that? The name of a breaktable is never used as a C identifier. It is simply a string.

Such breaking changes are very inconvenient, as they require to change all the templates where the name is used and make transition to EPICS 7 unnecessarily cumbersome.

Can we change it back?

diff --git a/modules/database/src/tools/DBD/Breaktable.pm b/modules/database/src/tools/DBD/Breaktable.pm

index 54e699131..06dae996c 100644

--- a/modules/database/src/tools/DBD/Breaktable.pm

+++ b/modules/database/src/tools/DBD/Breaktable.pm

@@ -20,6 +20,20 @@ sub init {

     return $this;

 }

 

+# Override, breaktable names are not strict

+sub identifier {

+    my ($this, $id, $what) = @_;

+    confess "DBD::Breaktable::identifier: $what undefined!"

+        unless defined $id;

+    if ($id !~ m/^$RXname$/) {

+        my @message;

+        push @message, "A $what should contain only letters, digits and these",

+            "special characters: _ - : . [ ] < > ;" unless $warned++;

+        warnContext("Deprecated $what '$id'", @message);

+    }

+    return $id;

+}

+

 sub add_point {

     my ($this, $raw, $eng) = @_;

     confess "DBD::Breaktable::add_point: Raw value undefined!"