Go to Project > Build Settings > ARM GCC 4.8.4 > Linker > General > Additional Libraries. b. Type in the library name without prefix "lib" and suffix ".a" (for example, "libemf32nosnlfn.a" would be "emf32nosnlfn") see Figure 7. This is because GCC compiler will automatically add the “lib” prefix to the library name. Refer this thread too PSoc Creator 4.2 and .a lib .
How to change -mfloat-abi=softfp to -mfloat-abi=hard ？
Please refer to the following KBA for adding a library file to Creator: Adding .a Library File to PSoC Creator Project Using GCC Toolchain – KBA227572
PSoC Creator doesn't support hardfp directly. You need to export the project to a makefile project and then modify the VFP variable in the makefile. Please refer this KBA for more information: Enabling Hardware Floating Point Compilation for Arm Cortex-M4 in PSoC Creator™ - KBA222890