[net.bugs.v7] cc allows external identifiers not unique in first 7 characters

geoff (04/29/83)

The v7 C compiler does not complain about definitions of external
identifiers that are not unique in their first 7 characters.  The
assembler does complain, giving slightly cryptic `m' diagnostics.
Since many users never use the assembler directly, one would like the C
compiler to diagnose this problem within a single source file.  For
conflicts across source files, the loader will complain quite clearly.

A recent net.sources program contained code like

	char *format_a = "a";
	char *format_b = "b";
	char *format_c = "c";

These are all truncated to `format_' by the compiler, but it fails to
notice that they are identical after truncation.

Geoff Collyer, U. of Toronto