This patch adds semantics checks to make sure that compilation units containing more than one `requires` directive are correct, as well as making sure that they do not come after other constructs that are affected by this directive. Additionally, an issue parsing this directive is fixed, which makes sure that the source location of the `requires` clauses is available at the time of performing semantic checks for the purpose of error reporting.

This patch adds semantics checks to make sure that compilation units containing more than one `requires` directive are correct, as well as making sure that they do not come after other constructs that are affected by this directive. It also handles the `atomic_default_mem_order` clause by setting it in a rewrite step as an explicit memory order associated to all atomic operations that don't already specify it. The directive resolution step and the symbol details for function- and module- like PFT nodes are extended to accomodate the addition and propagation of information about 'requires' directives contained inside. This enables exporting 'requires' clauses to .mod files and accessing them through 'use' Fortran statements. Additionally, an issue parsing this directive is fixed, which makes sure that the source location of the `requires` clauses is available at the time of performing semantic checks for the purpose of error reporting.

This patch adds semantics checks to make sure that compilation units containing more than one `requires` directive are correct, as well as making sure that they do not come after other constructs that are affected by this directive. It also handles the `atomic_default_mem_order` clause by setting it in a rewrite step as an explicit memory order associated to all atomic operations that don't already specify it. The directive resolution step and the symbol details for function- and module- like PFT nodes are extended to accomodate the addition and propagation of information about 'requires' directives contained inside. This enables exporting 'requires' clauses to .mod files and accessing them through 'use' Fortran statements. Additionally, an issue parsing this directive is fixed, which makes sure that the source location of the `requires` clauses is available at the time of performing semantic checks for the purpose of error reporting.