Check fpu functions without setjmp/longjmp before testing the latter.

Use exit code 2 for setup failure and 1 for test fail.  Unfortunately
this regress is still failing.

1 files changed, 51 insertions, 0 deletions

diff --git a/src/regress/lib/libc/setjmp-fpu/fpu.c b/src/regress/lib/libc/setjmp-fpu/fpu.c
new file mode 100644
index 0000000000..fbfc85a8ef
--- /dev/null
+++ b/src/regress/lib/libc/setjmp-fpu/fpu.c
@@ -0,0 +1,51 @@
+/*      $OpenBSD: fpu.c,v 1.1 2020/01/16 13:04:02 bluhm Exp $   */
+
+#include <err.h>
+#include <fenv.h>
+#include <stdlib.h>
+
+int
+main(int argc, char *argv[])
+{
+        fexcept_t flag;
+        int rv;
+
+        /* Set up the FPU control word register. */
+        rv = fesetround(FE_UPWARD);
+        if (rv != 0)
+                errx(2, "fesetround FE_UPWARD returned %d", rv);
+        fedisableexcept(FE_ALL_EXCEPT);
+        feenableexcept(FE_DIVBYZERO);
+
+        /* Set the FPU exception flags. */
+        flag = FE_OVERFLOW;
+        rv = fesetexceptflag(&flag, FE_ALL_EXCEPT);
+        if (rv != 0)
+                errx(2, "fesetexceptflag returned %d", rv);
+
+        /* Schedule another process, to check if kernel preserves state. */
+        rv = system("true");
+        if (rv == -1)
+                err(2, "system");
+        if (rv != 0)
+                errx(2, "true: %d", rv);
+
+        /* Verify that the FPU control word is preserved. */
+        rv = fegetround();
+        if (rv != FE_UPWARD)
+                errx(1, "fegetround returned %d, not FE_UPWARD", rv);
+        rv = fegetexcept();
+        if (rv != FE_DIVBYZERO)
+                errx(1, "fegetexcept returned %d, not FE_DIVBYZERO",
+                    rv);
+
+        /* Verify that the FPU exception flags weren't clobbered. */
+        flag = 0;
+        rv = fegetexceptflag(&flag, FE_ALL_EXCEPT);
+        if (rv != 0)
+                errx(2, "fegetexceptflag returned %d", rv);
+        if (flag != FE_OVERFLOW)
+                errx(1, "except flag is %d, no FE_OVERFLOW", rv);
+
+        return (0);
+}