No there would be no licensing issues. Although GCC is licensed under the GPL that only covers the code of the compiler itself not the code you write yourself. The code you write is licensed under whatever terms you choose and then the executable code produced by using GCC to compile that source code effectively uses the same license as our source code itself rather than the license of the GCC.
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GCC would be fairly useless if it restricted the terms under which you licensed your own software.