tablegen: Don't use cbrtf in host tools

You cannot count on them being present on all systems, and you
cannot include libm.h in a host tool, so just hard code baseline
implementations.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/libavcodec/cbrt_tablegen.h b/libavcodec/cbrt_tablegen.h
index 01963a3f9d..60d900a94f 100644
--- a/libavcodec/cbrt_tablegen.h
+++ b/libavcodec/cbrt_tablegen.h
@@ -36,12 +36,13 @@ static void cbrt_tableinit(void)
 {
     if (!cbrt_tab[(1<<13) - 1]) {
         int i;
+        /* cbrtf() isn't available on all systems, so we use powf(). */
         for (i = 0; i < 1<<13; i++) {
             union {
                 float f;
                 uint32_t i;
             } f;
-            f.f = cbrtf(i) * i;
+            f.f = powf(i, 1.0 / 3.0) * i;
             cbrt_tab[i] = f.i;
         }
     }