From 65c5b1eb85f8f0f3078f614d549f107ee9a001af Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Mon, 7 Jan 2019 22:39:43 +0000 Subject: [PATCH] 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. PR c/88720 PR c/88726 gcc/c: * 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: * gcc.dg/inline-40.c, gcc.dg/inline-41.c: New tests. From-SVN: r267665 --- gcc/c/ChangeLog | 9 ++++++ gcc/c/c-decl.c | 5 ++-- gcc/testsuite/ChangeLog | 6 ++++ gcc/testsuite/gcc.dg/inline-40.c | 49 ++++++++++++++++++++++++++++++++ gcc/testsuite/gcc.dg/inline-41.c | 49 ++++++++++++++++++++++++++++++++ 5 files changed, 116 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/inline-40.c create mode 100644 gcc/testsuite/gcc.dg/inline-41.c diff --git a/gcc/c/ChangeLog b/gcc/c/ChangeLog index fbd94f5607c..5ee4b66c513 100644 --- a/gcc/c/ChangeLog +++ b/gcc/c/ChangeLog @@ -1,3 +1,12 @@ +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. + 2019-01-07 Jakub Jelinek PR c++/85052 diff --git a/gcc/c/c-decl.c b/gcc/c/c-decl.c index d7726fa0834..5c7232f3657 100644 --- a/gcc/c/c-decl.c +++ b/gcc/c/c-decl.c @@ -1251,8 +1251,9 @@ pop_scope (void) && DECL_ABSTRACT_ORIGIN (p) != NULL_TREE && 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) { @@ -1268,7 +1269,7 @@ 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 29b3b835acc..ebc96a331bc 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,9 @@ +2019-01-07 Joseph Myers + + PR c/88720 + PR c/88726 + * gcc.dg/inline-40.c, gcc.dg/inline-41.c: New tests. + 2019-01-07 Paolo Carlini * g++.dg/diagnostic/constexpr1.C: New. diff --git a/gcc/testsuite/gcc.dg/inline-40.c b/gcc/testsuite/gcc.dg/inline-40.c new file mode 100644 index 00000000000..d0fdaeef34a --- /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 00000000000..1511aeebd58 --- /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) +{ +} -- 2.30.2