Merge pull request #10643 from CodaFi/distant-early-warning
diff --git a/include/swift/AST/DiagnosticsFrontend.def b/include/swift/AST/DiagnosticsFrontend.def
index ed7cb33..e098c22 100644
--- a/include/swift/AST/DiagnosticsFrontend.def
+++ b/include/swift/AST/DiagnosticsFrontend.def
@@ -198,9 +198,9 @@
"conditional compilation flags must be valid Swift identifiers (rather than '%0')",
(StringRef))
-ERROR(cannot_assign_value_to_conditional_compilation_flag,none,
- "conditional compilation flags do not have values in Swift; they are either present or absent"
- " (rather than '%0')", (StringRef))
+WARNING(cannot_assign_value_to_conditional_compilation_flag,none,
+ "conditional compilation flags do not have values in Swift; they are "
+ "either present or absent (rather than '%0')", (StringRef))
#ifndef DIAG_NO_UNDEF
# if defined(DIAG)
diff --git a/test/Frontend/unknown-arguments.swift b/test/Frontend/unknown-arguments.swift
index 0e681b2..e8f8553 100644
--- a/test/Frontend/unknown-arguments.swift
+++ b/test/Frontend/unknown-arguments.swift
@@ -9,6 +9,6 @@
// RUN: not %swiftc_driver -D Correct -DAlsoCorrect -D@#%! -D Swift=Cool -D-D -c %s -o %t.o 2>&1 | %FileCheck -check-prefix=INVALID-COND %s
// INVALID-COND: <unknown>:0: error: conditional compilation flags must be valid Swift identifiers (rather than '@#%!')
-// INVALID-COND-NEXT: <unknown>:0: error: conditional compilation flags do not have values in Swift; they are either present or absent (rather than 'Swift=Cool')
+// INVALID-COND-NEXT: <unknown>:0: warning: conditional compilation flags do not have values in Swift; they are either present or absent (rather than 'Swift=Cool')
// INVALID-COND-NEXT: <unknown>:0: error: conditional compilation flags must be valid Swift identifiers (rather than '-D')
