diff --git a/src/util/format/u_format_pack.py b/src/util/format/u_format_pack.py
index 57434adcd8c..874604c80ce 100644
--- a/src/util/format/u_format_pack.py
+++ b/src/util/format/u_format_pack.py
@@ -256,6 +256,10 @@ def native_to_constant(type, value):
             return "%.1ff" % float(value)
         else:
             return "%.1f" % float(value)
+    elif value == -2147483648:
+        return "INT_MIN"
+    elif value == -9223372036854775808:
+        return "INT64_MIN"
     else:
         return str(int(value))
 
diff --git a/src/util/softfloat.c b/src/util/softfloat.c
index 995e9825166..eb191a4ac1e 100644
--- a/src/util/softfloat.c
+++ b/src/util/softfloat.c
@@ -96,7 +96,7 @@ uint64_t _mesa_short_shift_right_jam64(uint64_t a, uint8_t dist)
  * From softfloat_shiftRightJam64()
  */
 static inline
-uint64_t _mesa_shift_right_jam64(uint64_t a, uint32_t dist)
+uint64_t _mesa_shift_right_jam64(uint64_t a, int32_t dist)
 {
     return
         (dist < 63) ? a >> dist | ((uint64_t) (a << (-dist & 63)) != 0) : (a != 0);
@@ -1339,7 +1339,7 @@ _mesa_float_fma_rtz(float a, float b, float c)
             }
             if (m_64 & 0x8000000000000000) {
                 s = !s;
-                m_64 = -m_64;
+                m_64 = (uint64_t)(-(int64_t)m_64);
             }
         } else {
             m_64 -= _mesa_shift_right_jam64(c_flt_m_64, exp_diff);