1 files changed, 41 insertions, 0 deletions
diff --git a/clang/test/Headers/floatneeds.c b/clang/test/Headers/floatneeds.c
new file mode 100644
index 0000000..e544b41
--- /dev/null
+++ b/clang/test/Headers/floatneeds.c
@@ -0,0 +1,41 @@
+// RUN: rm -fR %t
+// RUN: split-file %s %t
+// RUN: %clang_cc1 -fsyntax-only -verify=c99 -std=c99 %t/floatneeds0.c
+// RUN: %clang_cc1 -fsyntax-only -verify=c99 -std=c99 %t/floatneeds1.c
+// RUN: %clang_cc1 -fsyntax-only -verify=c23 -std=c23 %t/floatneeds0.c
+// RUN: %clang_cc1 -fsyntax-only -verify=c23 -std=c23 %t/floatneeds1.c
+// RUN: %clang_cc1 -fsyntax-only -verify=c99-modules -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -std=c99 %t/floatneeds0.c
+// RUN: %clang_cc1 -fsyntax-only -verify=c99-modules -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -std=c99 %t/floatneeds1.c
+// RUN: %clang_cc1 -fsyntax-only -verify=c23-modules -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -std=c23 %t/floatneeds0.c
+// RUN: %clang_cc1 -fsyntax-only -verify=c23-modules -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -std=c23 %t/floatneeds1.c
+
+// Use C99 to verify that __need_ can be used to get types that wouldn't normally be available.
+
+//--- floatneeds0.c
+float infinity0 = INFINITY; // c99-error{{undeclared identifier 'INFINITY'}} c23-error{{undeclared identifier 'INFINITY'}} \
+                               c99-modules-error{{undeclared identifier 'INFINITY'}} c23-modules-error{{undeclared identifier 'INFINITY'}}
+float nan0 = NAN; // c99-error{{undeclared identifier 'NAN'}} c23-error{{undeclared identifier 'NAN'}} \
+                     c99-modules-error{{undeclared identifier 'NAN'}} c23-modules-error{{undeclared identifier 'NAN'}}
+float max0 = FLT_MAX; // c99-error{{undeclared identifier 'FLT_MAX'}} c23-error{{undeclared identifier 'FLT_MAX'}} \
+                         c99-modules-error{{undeclared identifier 'FLT_MAX'}} c23-modules-error{{undeclared identifier 'FLT_MAX'}}
+
+#define __need_infinity_nan
+#include <float.h>
+float infinity1 = INFINITY;
+float nan1 = NAN;
+float max1 = FLT_MAX; // c99-error{{undeclared identifier}} c23-error{{undeclared identifier}} \
+                         c99-modules-error{{undeclared identifier}} c23-modules-error{{undeclared identifier}}
+
+#include <float.h>
+float infinity2 = INFINITY;
+float nan2 = NAN;
+float max2 = FLT_MAX;
+
+//--- floatneeds1.c
+// c23-no-diagnostics
+// c23-modules-no-diagnostics
+
+#include <float.h>
+float infinity0 = INFINITY; // c99-error{{undeclared identifier}} c99-modules-error{{undeclared identifier}}
+float nan0 = NAN; // c99-error{{undeclared identifier}} c99-modules-error{{undeclared identifier}}
+float max0 = FLT_MAX;