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The C99 standard requires type identifiers and forbids implicit function declarations. After issuing the diagnostic, an implementation may choose to assume an implicit declaration and continue translation to support existing programs that used this feature.
Noncompliant Code Example (
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Implicit int)
C90 Section 6.5.2 allows for the absence of type specifiers in a declaration. In these cases, the type is defined to be that of a signed int.
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