This is a patch that was approved a long time ago here: http://gcc.gnu.org/ml/gcc-patches/2011-01/msg01833.html but was never submitted.
2011-08-09 Artjoms Sinkarovs <artyom.shinakr...@gmail.com> /gcc * c-typeck.c (scalar_to_vector): New function. Try scalar to vector conversion. (stv_conv): New enum for scalar_to_vector return type. (build_binary_op): Adjust. * doc/extend.texi: Description of scalar to vector expansion. /gcc/c-family * c-common.c (unsafe_conversion_p): New function. Check if it is unsafe to convert an expression to the type. (conversion_warning): Adjust, use unsafe_conversion_p. * c-common.h (unsafe_conversion_p): New function declaration. /gcc/testsuite * gcc.c-torture/execute/scal-to-vec1.c: New test. * gcc.c-torture/execute/scal-to-vec2.c: New test. * gcc.c-torture/execute/scal-to-vec3.c: New test. * gcc.dg/scal-to-vec1.c: New test. * gcc.dg/scal-to-vec2.c: New test. bootstrapped and tested on x86_64_unknown-linux Thanks, Artem.
