When building an ios project you may get an error along the lines C PREPROCESS missing FILENAME.
To solve this, check your project definition for INFOPLIST_PREFIX_HEADER = "${BUILD_DIR}/GeneratedInfoPlistDotEnv.h"; has no other characters for instance "\n" which was causing my issue.
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To solve this, check your project definition for
INFOPLIST_PREFIX_HEADER = "${BUILD_DIR}/GeneratedInfoPlistDotEnv.h";has no other characters for instance"\n"which was causing my issue.