+/**
+ * STDC pragmas.
+ */
+typedef enum {
+ STDC_UNKNOWN,
+ STDC_FP_CONTRACT,
+ STDC_FENV_ACCESS,
+ STDC_CX_LIMITED_RANGE
+} stdc_pragma_kind_t;
+
+/**
+ * STDC pragma values.
+ */
+typedef enum {
+ STDC_VALUE_UNKNOWN,
+ STDC_VALUE_ON,
+ STDC_VALUE_OFF,
+ STDC_VALUE_DEFAULT
+} stdc_pragma_value_kind_t;
+
+/**
+ * Parse a pragma directive.
+ */
+static void parse_pragma(void) {
+ bool unknown_pragma = true;
+
+ next_pp_token();
+ if (pp_token.v.symbol->pp_ID == TP_STDC) {
+ stdc_pragma_kind_t kind = STDC_UNKNOWN;
+ /* a STDC pragma */
+ if (c_mode & _C99) {
+ next_pp_token();
+
+ switch (pp_token.v.symbol->pp_ID) {
+ case TP_FP_CONTRACT:
+ kind = STDC_FP_CONTRACT;
+ break;
+ case TP_FENV_ACCESS:
+ kind = STDC_FENV_ACCESS;
+ break;
+ case TP_CX_LIMITED_RANGE:
+ kind = STDC_CX_LIMITED_RANGE;
+ break;
+ default:
+ break;
+ }
+ if (kind != STDC_UNKNOWN) {
+ stdc_pragma_value_kind_t value = STDC_VALUE_UNKNOWN;
+ next_pp_token();
+ switch (pp_token.v.symbol->pp_ID) {
+ case TP_ON:
+ value = STDC_VALUE_ON;
+ break;
+ case TP_OFF:
+ value = STDC_VALUE_OFF;
+ break;
+ case TP_DEFAULT:
+ value = STDC_VALUE_DEFAULT;
+ break;
+ default:
+ break;
+ }
+ if (value != STDC_VALUE_UNKNOWN) {
+ unknown_pragma = false;
+ } else {
+ errorf(pp_token.source_position, "bad STDC pragma argument");
+ }
+ }
+ }
+ } else {
+ unknown_pragma = true;
+ }
+ eat_until_newline();
+ if (unknown_pragma && warning.unknown_pragmas) {
+ warningf(pp_token.source_position, "encountered unknown #pragma");
+ }
+}
+
+/**
+ * Parse a preprocessor non-null directive.
+ */