250814.233734.CST [skip ci] update Makefile.common

Author: zaikunzhang

fortran/tests/makefiles/Makefile.common

@@ -92,7 +92,7 @@ endif
 # Define the compiler-dependent "fast flags", which will be used when FFLAGS is -fast.
 AFF := -O4
 DFF := -O4 -Ofast -ffast-math  # As of AOCC 4.2, -Ofast implies -O3, but it is not clear whether it implies -ffast-math
-FFF := -O3 -Ofast -ffast-math  # No documentation found about the relation between -Ofast, -O3, and -ffast-math
+FFF := -O3 -ffast-math -fstack-arrays  # Suggested by flang 20.1.7
 GFF := -Ofast  # -Ofast implies -O3 and -ffast-math
 NFF := -O4
 RFF := -Ofast -ffast-math # -Ofast implies -O3, but no documentation found about the relation between -Ofast and -ffast-math