How Does GCC Find Standard Include Paths Without Explicit Specification?

Discovering GCC's Default Include Paths

When compiling source code without specifying standard include files like stdio or stdlib, GCC magically locates them. How does it achieve this?

To determine the default search paths and their priorities, execute the following commands:

For C:

echo | gcc -xc -E -v -

For C :

echo | gcc -xc++ -E -v -

The credit belongs to the Qt Creator team. Here's a breakdown of the flags:

• -x: selects C or C
• -E: enables preprocessing only
• -v: prints executed commands
• -: pipes an empty string to GCC

The output will display the standard paths used by GCC. These paths are typically hardcoded within the compiler, ensuring it can locate necessary headers without additional user input.

The above is the detailed content of How Does GCC Find Standard Include Paths Without Explicit Specification?. For more information, please follow other related articles on the PHP Chinese website!