From: Joseph Myers Date: Wed, 16 Jan 2019 21:40:33 +0000 (+0000) Subject: Fix diagnostics for never-defined inline and nested functions (PR c/88720, PR c/88726). X-Git-Tag: releases/gcc-7.5.0~655 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=10396eea184b75aa05c6050479b748dfe8a6978d;p=thirdparty%2Fgcc.git Fix diagnostics for never-defined inline and nested functions (PR c/88720, PR c/88726). Bugs 88720 and 88726 report issues where a function is declared inline in an inner scope, resulting in spurious diagnostics about it being declared but never defined when that scope is left (possibly in some cases also wrongly referring to the function as a nested function). These are regressions that were introduced with the support for C99 inline semantics in 4.3 (they don't appear with 4.2; it's possible some aspects of the bugs might have been introduced later than 4.3). For the case of functions being wrongly referred to as nested, DECL_EXTERNAL was not the right condition for a function being non-nested; TREE_PUBLIC is appropriate for the case of non-nested functions with external linkage, while !b->nested means this is the outermost scope in which the function was declared and so avoids catching the case of a file-scope static being redeclared inline inside a function. For the non-nested, external-linkage case, the code attempts to avoid duplicate diagnostics by diagnosing only when scope != external_scope, but actually scope == external_scope is more appropriate, as it's only when the file and external scopes are popped that the code can actually tell whether a function ended up being defined, and all such functions will appear in the (GCC-internal) external scope. Bootstrapped with no regressions on x86_64-pc-linux-gnu. gcc/c: Backport from mainline 2019-01-07 Joseph Myers PR c/88720 PR c/88726 * c-decl.c (pop_scope): Use TREE_PUBLIC and b->nested to determine whether a function is nested, not DECL_EXTERNAL. Diagnose inline functions declared but never defined only for external scope, not for other scopes. gcc/testsuite: Backport from mainline 2019-01-07 Joseph Myers PR c/88720 PR c/88726 * gcc.dg/inline-40.c, gcc.dg/inline-41.c: New tests. From-SVN: r267987 --- diff --git a/gcc/c/ChangeLog b/gcc/c/ChangeLog index 86a4c9659736..ab2eae1ff375 100644 --- a/gcc/c/ChangeLog +++ b/gcc/c/ChangeLog @@ -1,3 +1,15 @@ +2019-01-16 Joseph Myers + + Backport from mainline + 2019-01-07 Joseph Myers + + PR c/88720 + PR c/88726 + * c-decl.c (pop_scope): Use TREE_PUBLIC and b->nested to determine + whether a function is nested, not DECL_EXTERNAL. Diagnose inline + functions declared but never defined only for external scope, not + for other scopes. + 2018-01-02 Segher Boessenkool Backport from trunk diff --git a/gcc/c/c-decl.c b/gcc/c/c-decl.c index ed609d29f96b..14a3832f7bf9 100644 --- a/gcc/c/c-decl.c +++ b/gcc/c/c-decl.c @@ -1235,8 +1235,9 @@ pop_scope (void) && DECL_ABSTRACT_ORIGIN (p) != 0 && DECL_ABSTRACT_ORIGIN (p) != p) TREE_ADDRESSABLE (DECL_ABSTRACT_ORIGIN (p)) = 1; - if (!DECL_EXTERNAL (p) + if (!TREE_PUBLIC (p) && !DECL_INITIAL (p) + && !b->nested && scope != file_scope && scope != external_scope) { @@ -1252,7 +1253,7 @@ pop_scope (void) in the same translation unit." */ if (!flag_gnu89_inline && !lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (p)) - && scope != external_scope) + && scope == external_scope) pedwarn (input_location, 0, "inline function %q+D declared but never defined", p); DECL_EXTERNAL (p) = 1; diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index af4e7a338a8b..15a4270d9399 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,12 @@ +2019-01-16 Joseph Myers + + Backport from mainline + 2019-01-07 Joseph Myers + + PR c/88720 + PR c/88726 + * gcc.dg/inline-40.c, gcc.dg/inline-41.c: New tests. + 2019-01-16 Martin Jambor Backported from mainline diff --git a/gcc/testsuite/gcc.dg/inline-40.c b/gcc/testsuite/gcc.dg/inline-40.c new file mode 100644 index 000000000000..d0fdaeef34a3 --- /dev/null +++ b/gcc/testsuite/gcc.dg/inline-40.c @@ -0,0 +1,49 @@ +/* Test inline functions declared in inner scopes. Bugs 88720 and 88726. */ +/* { dg-do compile } */ +/* { dg-options "" } */ + +void +inline_1 (void) +{ +} + +void +inline_2 (void) +{ +} + +static void +inline_static_1 (void) +{ +} + +static void +inline_static_2 (void) +{ +} + +static void inline_static_3 (void); +static void inline_static_4 (void); + +static void +test (void) +{ + inline void inline_1 (void); + extern inline void inline_2 (void); + inline void inline_3 (void); + extern inline void inline_4 (void); + inline void inline_static_1 (void); + extern inline void inline_static_2 (void); + inline void inline_static_3 (void); + extern inline void inline_static_4 (void); +} + +void +inline_3 (void) +{ +} + +void +inline_4 (void) +{ +} diff --git a/gcc/testsuite/gcc.dg/inline-41.c b/gcc/testsuite/gcc.dg/inline-41.c new file mode 100644 index 000000000000..1511aeebd582 --- /dev/null +++ b/gcc/testsuite/gcc.dg/inline-41.c @@ -0,0 +1,49 @@ +/* Test inline functions declared in inner scopes. Bugs 88720 and 88726. */ +/* { dg-do compile } */ +/* { dg-options "-fgnu89-inline" } */ + +void +inline_1 (void) +{ +} + +void +inline_2 (void) +{ +} + +static void +inline_static_1 (void) +{ +} + +static void +inline_static_2 (void) +{ +} + +static void inline_static_3 (void); +static void inline_static_4 (void); + +static void +test (void) +{ + inline void inline_1 (void); + extern inline void inline_2 (void); + inline void inline_3 (void); + extern inline void inline_4 (void); + inline void inline_static_1 (void); + extern inline void inline_static_2 (void); + inline void inline_static_3 (void); + extern inline void inline_static_4 (void); +} + +void +inline_3 (void) +{ +} + +void +inline_4 (void) +{ +}